Chemistry: Hydrocarbon Structures

C2H2

Triple bond

Three

<p>Unsaturated carbon compounds</p> Signup and view all the answers

<p>Unsaturated carbon compounds are more reactive</p> Signup and view all the answers

<p>Propane</p> Signup and view all the answers

<p>C6H14</p> Signup and view all the answers

<p>12</p> Signup and view all the answers

<p>Methane</p> Signup and view all the answers

<p>Hydrocarbons</p> Signup and view all the answers

<p>Ethene has a double bond between the carbon atoms, while ethyne has a triple bond. The triple bond in ethyne is stronger and shorter than the double bond in ethene, making ethyne more reactive and less stable.</p> Signup and view all the answers

<p>Ethyne is unsaturated because it has a triple bond between the carbon atoms, meaning it has fewer hydrogen atoms than it could have if all the carbon-carbon bonds were single bonds. Methane is saturated because all carbon-carbon bonds are single bonds, and it contains the maximum number of hydrogen atoms possible.</p> Signup and view all the answers

<p>CnH2n+2</p> Signup and view all the answers

<p>C7H16. Since it is a saturated hydrocarbon, it follows the general formula CnH2n+2. With 7 carbon atoms (n=7), the formula becomes C7H14+2, or C7H16.</p> Signup and view all the answers

<p>Unsaturated hydrocarbons contain double or triple bonds between carbon atoms, which are weaker than single bonds and therefore more susceptible to breaking. This makes them more reactive.</p> Signup and view all the answers

<p>Propane has three carbon atoms connected by single bonds, with each carbon atom having four single bonds to hydrogen atoms. Ethane only has two carbon atoms connected by a single bond, with six single bonds to hydrogen atoms.</p> Signup and view all the answers

<p>C8H18. As the general formula is CnH2n+2, with 8 carbon atoms, the formula becomes C8H16+2 = C8H18.</p> Signup and view all the answers

<p>They are classified as saturated hydrocarbons because they contain only single bonds between carbon atoms. This means each carbon atom has formed the maximum possible number of bonds with hydrogen atoms, leading to a 'saturated' structure.</p> Signup and view all the answers

<p>Saturated compounds, like methane and ethane, have only single bonds between carbon atoms, while unsaturated compounds, like ethene and ethyne, have at least one double or triple bond between carbon atoms. This allows them to react further and add more hydrogen atoms, making them unsaturated.</p> Signup and view all the answers

<p>Butene is likely to be more reactive than butane. Butene, with a double bond, is unsaturated and thus has more reactive sites than butane, which is saturated due to single bonds between carbon atoms.</p> Signup and view all the answers

<p>Ethyne is unsaturated because it has a triple bond between the two carbon atoms, leaving fewer potential bonding sites for hydrogen atoms compared to methane, which has only single bonds between carbon and hydrogen. This means ethyne is classified as unsaturated, whereas methane is saturated due to the presence of only single bonds.</p> Signup and view all the answers

<p>The general formula for a saturated hydrocarbon with 'n' carbon atoms is CnH2n+2. This is based on the observation that each carbon atom forms four single bonds (4 hydrogen atoms for the first carbon atom, then two for each additional carbon atom).</p> Signup and view all the answers

<p>The molecular formula for a saturated hydrocarbon with seven carbon atoms would be C7H16. This can be derived by applying the general formula CnH2n+2, where 'n' is the number of carbon atoms. Substituting '7' for 'n', we get C7H14+2, resulting in C7H16.</p> Signup and view all the answers

<p>Unsaturated hydrocarbons are generally more reactive as they have double or triple bonds, which are weaker than single bonds. These multiple bonds introduce areas of 'electron density' that can be more readily attacked or disrupted by other molecules, leading to reactions. Saturated hydrocarbons, on the other hand, have only single bonds, and their carbon atoms are all bonded to the maximum number of hydrogen atoms, making them relatively less reactive.</p> Signup and view all the answers

<p>Propane has three carbon atoms, each forming four bonds. Two of the carbon atoms are bonded to three hydrogens and one other carbon atom, each forming four single bonds. The central carbon atom is bonded to two hydrogens and two carbon atoms. This structure differs from ethane by the addition of an extra carbon atom, which increases the length of the carbon chain, and the number of hydrogen atoms.</p> Signup and view all the answers

<p>A saturated carbon compound contains only single bonds between carbon atoms, while an unsaturated carbon compound contains at least one double or triple bond between carbon atoms. For example, ethane (C2H6) is saturated as it only contains single bonds between carbon atoms, while ethyne (C2H2) is unsaturated due to the triple bond between the carbon atoms. This difference in bonding alters the number of hydrogen atoms attached to the carbon chain.</p> Signup and view all the answers

<p>Butane is expected to be less reactive than butene. Butane is a saturated hydrocarbon, while butene is unsaturated due to the presence of a double bond. This double bond in butene makes it more prone to react compared to butane, which has only single bonds.</p> Signup and view all the answers

<p>The electron dot structure of ethene shows a double bond between the two carbon atoms, while ethyne exhibits a triple bond between the carbon atoms. These differences in bonding result in ethyne being more reactive than ethene. The triple bond in ethyne creates greater electron density and a higher degree of unsaturation, making it more susceptible to chemical attack or reactions. Compared to ethene, ethyne’s stronger triple bond also makes it more stable in reactions.</p> Signup and view all the answers

<p>Structural isomers are compounds with the same molecular formula but different structural arrangements of atoms.</p> Signup and view all the answers

<p>Cyclohexane is saturated because all its carbon atoms form single bonds with other carbons and hydrogen atoms.</p> Signup and view all the answers

<p>Alkanes are saturated hydrocarbons with only single bonds. Alkenes have one or more double bonds. Alkynes have one or more triple bonds.</p> Signup and view all the answers

<p>Hydrocarbons</p> Signup and view all the answers

<p>Butane (C4H10)</p> Signup and view all the answers

<p>Unsaturated hydrocarbons have double or triple bonds which are weaker and more reactive than single bonds.</p> Signup and view all the answers

<p>The electron dot structure of methane (CH4) has a central carbon atom with four hydrogen atoms surrounding it, each bonded by a single covalent bond. Each carbon atom shares its four valence electrons to form four single bonds, satisfying the octet rule for all atoms involved. This structure can be represented as follows: H H │ │ C - H H</p> Signup and view all the answers

<p>CnH2n+2</p> Signup and view all the answers

<p>The simplest alkane is methane, with the molecular formula CH4.</p> Signup and view all the answers

<p>The two isomers of butane differ in the arrangement of their carbon atoms. One isomer has a straight chain of four carbon atoms, while the other has a branched chain with three carbon atoms in a row and the fourth attached as a side branch. They are considered structural isomers because they have the same molecular formula (C4H10) but different structural arrangements.</p> Signup and view all the answers

<p>Alkanes are saturated hydrocarbons, meaning they only contain single bonds between carbon atoms. Alkenes have at least one double bond between carbon atoms, and alkynes have at least one triple bond between carbon atoms. The presence of double or triple bonds (unsaturated) makes alkenes and alkynes more reactive than alkanes.</p> Signup and view all the answers

<p>Unsaturated hydrocarbons, like ethene, have double or triple bonds between carbon atoms. These bonds are weaker than single bonds, making them more susceptible to breaking and undergoing reactions. Saturated hydrocarbons, like ethane, only have single bonds, making them more stable and less reactive.</p> Signup and view all the answers

<p>Carbon's ability to form up to four bonds allows it to bond with other carbon atoms to form long chains, branched chains, and rings. The different ways these chains can be arranged with the same number of carbon and hydrogen atoms, leads to the formation of structural isomers.</p> Signup and view all the answers

<p>A straight-chain hydrocarbon has all carbon atoms connected in a single line, like butane (C4H10) with four carbon atoms in a row. A branched-chain hydrocarbon has one or more carbon atoms branching off the main chain, like isobutane (C4H10) with three carbon atoms in a row and a fourth branching off the second carbon.</p> Signup and view all the answers

<p>The molecular formula for a saturated hydrocarbon with 10 carbon atoms would be C10H22. Each carbon atom in a saturated hydrocarbon forms four single bonds, with two hydrogen atoms for each internal carbon and three hydrogen atoms for the two terminal carbons. This gives the general formula CnH2n+2, where n is the number of carbon atoms.</p> Signup and view all the answers

<p>The electron dot structure for benzene shows a ring of six carbon atoms, with alternating single and double bonds. These double bonds are not fixed in their position, but instead, the electrons are delocalized across the entire ring, giving rise to a resonance structure. This delocalization of electrons contributes to the stability of the benzene molecule.</p> Signup and view all the answers

<p>Cyclohexane is an example of a cyclic hydrocarbon. It consists of six carbon atoms joined in a ring, forming a stable cyclic structure. This type of structure significantly alters the properties of the compound compared to linear hydrocarbons with the same number of carbon atoms.</p> Signup and view all the answers

<p>A hydrocarbon containing only single bonds between carbon atoms is classified as a saturated hydrocarbon. An example is methane (CH4), the simplest alkane.</p> Signup and view all the answers

<p>Cyclohexane is classified as a saturated hydrocarbon because it only contains single bonds between carbon atoms. The ring structure itself does not change the fact that all carbon atoms are bonded to the maximum number of hydrogen atoms possible, with no double or triple bonds present.</p> Signup and view all the answers

<p>Carbon's ability to form four bonds allows it to attach to multiple other carbon atoms, creating chains of varying lengths and arrangements. This flexibility in bonding leads to the formation of different structures with the same molecular formula, which are known as structural isomers. The text illustrates this with the example of butane (C4H10) where two different structures are possible: a straight chain and a branched chain. This demonstrates how carbon's bonding capacity enables the creation of multiple structural arrangements for a given molecular formula.</p> Signup and view all the answers

<p>Alkanes are saturated hydrocarbons containing only single bonds between carbon atoms. Alkenes have at least one double bond between carbon atoms, while alkynes have at least one triple bond between carbon atoms. This difference in bonding makes alkanes more stable and less reactive than alkenes and alkynes. Alkenes and alkynes are considered unsaturated hydrocarbons due to the presence of double or triple bonds, which make them more reactive than their saturated counterparts. The text highlights this difference in reactivity by discussing how unsaturated hydrocarbons are generally more reactive than their saturated counterparts, due to the presence of double or triple bonds.</p> Signup and view all the answers

<p>Benzene's structure is unique because it consists of a six-membered ring with alternating single and double bonds between carbon atoms. This arrangement creates a delocalized electron system, meaning that the electrons are not localized between specific atoms but rather spread out over the entire ring. This delocalization of electrons contributes to the exceptional stability of benzene, making it less reactive than typical unsaturated hydrocarbons like alkenes and alkynes.</p> Signup and view all the answers

<p>Ethene (C2H4) has a double bond between the two carbon atoms, while ethyne (C2H2) has a triple bond between the two carbon atoms. This difference in bonding affects their reactivity. Ethene is more reactive than ethane due to the presence of the double bond, making it susceptible to addition reactions. Ethyne, with its triple bond, is even more reactive than ethene because the stronger bond allows for a greater variety of reactions, including addition and substitution reactions. Their reactivity is directly related to the number of bonds between the shared carbon atoms, impacting their ability to participate in chemical reactions.</p> Signup and view all the answers

<p>The general formula for a saturated hydrocarbon is CnH2n+2. Therefore, a saturated hydrocarbon with 10 carbon atoms would have the molecular formula C10H22. This is because the formula reflects the fact that each carbon atom in a saturated hydrocarbon forms four single bonds, two with hydrogen atoms and two with other carbon atoms. This leads to a specific ratio of hydrogen atoms to carbon atoms within a molecule, governed by the general formula.</p> Signup and view all the answers

<p>A straight-chain hydrocarbon has carbon atoms linked in a continuous chain, while a branched-chain hydrocarbon has one or more carbon atoms branching off the main chain. For example, butane (C4H10) has a straight-chain structure, where all four carbon atoms are connected in a row. However, isobutane (also C4H10) is a branched-chain hydrocarbon with three carbon atoms in a row and one carbon atom branching off the second carbon atom in the chain. This difference in structure is reflected in the arrangement of carbon atoms within the molecule and leads to different physical and chemical properties.</p> Signup and view all the answers

<p>Unsaturated hydrocarbons contain double or triple bonds between carbon atoms, which are weaker than single bonds found in saturated hydrocarbons. This makes unsaturated hydrocarbons more prone to breaking and forming new bonds, thus making them more reactive. Ethene (C2H4), with its double bond, is more reactive than ethane (C2H6) because the double bond is a weaker bond, easily broken and rearranged through addition reactions. The presence of double or triple bonds introduces a 'reactive site' where additional atoms or molecules can attach, increasing their reactivity compared to saturated hydrocarbons.</p> Signup and view all the answers

<p>Cyclohexane is classified as a saturated hydrocarbon because it only possesses single bonds between its carbon atoms. Despite its ring structure, all the carbon atoms are linked by single covalent bonds, satisfying their valencies and preventing any C=C or C≡C bonds. The absence of double or triple bonds, the characteristic feature of unsaturated hydrocarbons, makes cyclohexane a saturated hydrocarbon, indicating the presence of single bonds only.</p> Signup and view all the answers

<p>Alkanes are saturated hydrocarbons containing single bonds between carbon atoms. Alkenes have one or more double bonds between carbon atoms, while alkynes have at least one triple bond. This difference in bonding affects reactivity. Alkanes, with only single bonds, are more stable and less reactive than alkenes and alkynes. The presence of double or triple bonds in alkenes and alkynes makes them unsaturated and more reactive. The double or triple bonds are 'reactive sites' where new bonds can easily be formed, making them more susceptible to addition and substitution reactions. Thus, alkanes are generally less reactive than alkenes and alkynes.</p> Signup and view all the answers

<p>The electron dot structure for propane (C3H8) would show three carbon atoms connected in a chain and each carbon atom forming four single bonds. The central carbon atom is bonded to two hydrogen atoms and two other carbon atoms. The two outer carbon atoms each form bonds with three hydrogen atoms. Ethane (C2H6) has only two carbon atoms connected by a single bond and each carbon atom forming bonds with three hydrogen atoms. The difference lies in the number of carbon atoms in the chain and the resulting number of bonds. While ethane has two carbon atoms, propane has three, leading to a longer chain and different bonding patterns.</p> Signup and view all the answers

<p>-CH2-</p> Signup and view all the answers

<p>Hydroxyl group (-OH)</p> Signup and view all the answers

<p>C2H4</p> Signup and view all the answers

<p>14 u</p> Signup and view all the answers

<p>Heteroatoms are atoms such as halogens, oxygen, nitrogen, and sulfur that replace hydrogen in a hydrocarbon. They confer specific properties to the compound, regardless of the carbon chain's length and nature.</p> Signup and view all the answers

<p>The '-OH' functional group is known as the alcohol group. It is associated with alcohol compounds.</p> Signup and view all the answers

<p>Functional groups define the specific properties and reactivities of organic compounds. They dictate how compounds interact with each other and with other substances.</p> Signup and view all the answers

<p>The valency of carbon must remain satisfied when hydrogen is replaced by heteroatoms. This allows the compound to maintain its structural stability.</p> Signup and view all the answers

<p>The functional group for carboxylic acids is '-COOH'.</p> Signup and view all the answers

<p>Heteroatoms can introduce polar characteristics to a compound, making it more reactive due to the difference in electronegativity. This reactivity can lead to various chemical reactions that would not occur in saturated hydrocarbons.</p> Signup and view all the answers

<p>An example of a functional group associated with halogenated hydrocarbons is '-Cl' or '-Br'.</p> Signup and view all the answers

<p>Adding heteroatoms to a hydrocarbon chain generally increases its reactivity and introduces new properties. This modification can affect solubility, boiling points, and acidity.</p> Signup and view all the answers

<p>Aldehydes contain a carbonyl functional group represented as '-CHO', while alcohols contain a hydroxyl group represented as '-OH'.</p> Signup and view all the answers

<p>Functional groups are important because they determine the classification and properties of organic compounds, allowing chemists to predict their behavior in chemical reactions.</p> Signup and view all the answers

<p>A homologous series is a group of organic compounds with the same functional group and similar chemical properties, where each successive member differs by a CH2 unit.</p> Signup and view all the answers

<p>Butane has one additional –CH2– unit compared to propane. This difference in the number of carbon atoms leads to the difference in their molecular formulas.</p> Signup and view all the answers

<p>$14 u$</p> Signup and view all the answers

<p>They all belong to the same homologous series and share the same functional group, which is the hydroxyl (-OH) group, determining their chemical properties.</p> Signup and view all the answers

<p>CnH2n</p> Signup and view all the answers

<p>Propene has one additional –CH2– unit compared to ethene.</p> Signup and view all the answers

<p>Ethene contains a double bond between the carbon atoms, making it unsaturated. Ethane is saturated with only single bonds, leading to less reactivity in ethane.</p> Signup and view all the answers

<p>C2H2</p> Signup and view all the answers

<p>It provides a systematic way to understand the properties of organic compounds. The presence of the same functional group in a series leads to similar chemical properties, even with increasing chain length.</p> Signup and view all the answers

<p>CnH2n+2</p> Signup and view all the answers

<p>A heteroatom is an atom other than carbon or hydrogen in a molecule. They replace hydrogen in a hydrocarbon chain and contribute to the functional groups, which give a compound specific properties regardless of the length or nature of the carbon chain.</p> Signup and view all the answers

<p>Functional groups are important because they give a molecule specific properties, regardless of the length or nature of the carbon chain. They have the power to dramatically influence the chemical and physical characteristics of organic molecules.</p> Signup and view all the answers

<p>The bond between carbon atoms in hydrocarbons can be single, double, or triple bonds. The presence of a double or triple bond leads to unsaturated hydrocarbons, which are more reactive than saturated hydrocarbons with only single bonds. This impacts their reactivity and the chemical reactions they can undergo.</p> Signup and view all the answers

<p>A functional group is a specific group of heteroatoms, or a group of atoms containing a heteroatom, that confers specific properties to a carbon compound. Functional groups attach to the carbon chain by replacing one or more hydrogen atoms.</p> Signup and view all the answers

<p>Different functional groups impart distinct properties to organic molecules, influencing their physical characteristics (like melting point, boiling point, and solubility) and their chemical reactivity. For example, the presence of an alcohol functional group makes a compound more polar and soluble in water, while the presence of a carboxyl group makes a compound acidic.</p> Signup and view all the answers

<p>The hydroxyl group (-OH), found in alcohols, is a functional group. Compared to a simple hydrocarbon chain, the presence of a hydroxyl group makes the compound more polar and enhances its solubility in water. This is due to the ability of the hydroxyl group to form hydrogen bonds with water molecules.</p> Signup and view all the answers

<p>Functional groups are essential for classifying organic compounds. They provide a framework for organizing and categorizing organic molecules with similar properties. This classification makes the study and understanding of organic chemistry more efficient.</p> Signup and view all the answers

<p>Functional groups are essential for the structure, diversity, and function of biological systems. They are responsible for various biological processes including protein folding, enzyme catalysis, and the formation of complex biomolecules.</p> Signup and view all the answers

<p>The presence of a heteroatom can significantly affect the reactivity of a hydrocarbon. Introducing a heteroatom often introduces polarity and new reaction sites, making the molecule more reactive. For example, the presence of a hydroxyl group (-OH) in alcohol makes it more reactive than a corresponding alkane due to the presence of a polar functional group.</p> Signup and view all the answers

<p>The presence of a functional group can lead to different isomers of a compound by introducing a new point of variation in the molecule. The functional group can be attached to different positions in a carbon chain, resulting in different isomers with distinct properties.</p> Signup and view all the answers

<p>Functional groups contain heteroatoms, which influence the compound's reactivity and overall chemical behavior. The presence of a specific functional group consistently leads to the compound exhibiting characteristic properties, regardless of the chain length or structure. This is because the functional group's presence overrides the influence of the carbon chain in determining the compound's behavior.</p> Signup and view all the answers

<p>A heteroatom is an atom of an element other than carbon or hydrogen that is present in a carbon compound. It replaces a hydrogen atom in the hydrocarbon chain and alters the properties of the compound. For example, in an alcohol, the heteroatom is oxygen (O), which forms a hydroxyl group (-OH) and alters the compound's properties, making it more polar and reactive.</p> Signup and view all the answers

<p>Functional groups are termed &quot;functional&quot; because they define the compound's reactivity and overall behavior in chemical reactions. The specific arrangement of heteroatoms within a functional group dictates how the molecule interacts with other molecules and influences its chemical properties.</p> Signup and view all the answers

<p>A haloalkane is formed by replacing one or more hydrogen atoms in a hydrocarbon chain with a halogen atom (Cl or Br). This substitution introduces polarity to the molecule, as halogens are more electronegative than carbon and hydrogen. The polar nature of the haloalkane makes it more reactive than the original hydrocarbon due to the uneven electron distribution within the molecule.</p> Signup and view all the answers

<p>The hydroxyl group makes the compound more polar, due to the electronegative nature of oxygen. This polar character increases the compound's solubility in water and enhances its reactivity. The ability to form hydrogen bonds through the hydroxyl group also leads to stronger intermolecular interactions, influencing the compound's boiling and melting points.</p> Signup and view all the answers

<p>The arrangement of heteroatoms within a functional group creates a specific configuration that influences the compound's reactivity and overall behavior. The spatial arrangement of the atoms affects the polarity, bond strength, and overall electron distribution, leading to specific chemical and physical properties. For example, the presence of a carbonyl group (C=O) in a ketone versus an aldehyde leads to subtle, but significant, differences in the ability of each compound to donate or accept electrons.</p> Signup and view all the answers

<p>The presence and type of functional group present in a compound directly determine its reactivity. This reactivity is independent of the length and nature of the hydrocarbon chain, as the functional group's specific arrangement of atoms and bonds dictates the compound's interactions with other molecules.</p> Signup and view all the answers

<p>Heteroatoms, such as oxygen or halogens, exhibit higher electronegativity than carbon and hydrogen. This difference in electronegativity creates a dipole moment within the molecule as electrons are pulled closer to the heteroatom, generating a partial negative charge. This enhanced polarity makes the compound more reactive and water-soluble.</p> Signup and view all the answers

<p>The substitution of a hydrogen atom by a heteroatom is termed the creation of a &quot;functional group&quot; because this substitution brings about a significant change in the behavior of the compound. The functional group dictates the compound's chemical behavior, and reactivity, regardless of the chain length or structure of the hydrocarbon. The term &quot;functional group&quot; is used for this because these specific arrangements of atoms take on a role that determines the compound's functionality in reactions with other molecules.</p> Signup and view all the answers

<p>A homologous series in organic chemistry is a group of compounds with the same functional group but differing by a constant –CH2- unit in their molecular formula. For example, methane (CH4), ethane (C2H6), and propane (C3H8) form a homologous series, where each successive member has one additional –CH2- unit. This difference in structure leads to a gradual change in physical properties, like boiling point, while the chemical properties remain similar within the series.</p> Signup and view all the answers

<p>The molecular formula for the saturated hydrocarbon with nine carbon atoms would be C9H20. This is because the general formula for alkanes is CnH2n+2, where 'n' represents the number of carbon atoms. For a hydrocarbon with nine carbon atoms, the formula becomes C9H(2*9)+2, which simplifies to C9H20.</p> Signup and view all the answers

<p>Ethene (C2H4) has a double bond between the two carbon atoms, while ethyne (C2H2) has a triple bond between the carbon atoms. This difference in bonding means that ethene and ethyne are both unsaturated hydrocarbons, meaning they have fewer hydrogen atoms than a corresponding saturated hydrocarbon. The presence of multiple bonds in ethene and ethyne makes them more reactive than their saturated counterparts, as these multiple bonds can be broken to form new bonds. The triple bond in ethyne makes it even more reactive than ethene because of the higher concentration of electrons in the triple bond.</p> Signup and view all the answers

<p>Structural isomers are compounds with the same molecular formula but different structural arrangements. For example, ethane (C2H6) and propane (C3H8) only have one possible structure, as their carbon atoms are arranged in a linear chain. However, hydrocarbons with four or more carbon atoms can have different arrangements of carbon atoms, leading to multiple structural isomers. The ability of carbon to form four bonds allows for branching in the carbon chain, which results in different spatial arrangements of the atoms, even though the molecular formula remains the same.</p> Signup and view all the answers

<p>Saturated hydrocarbons, characterized by single bonds between all carbon atoms, are generally less reactive than unsaturated hydrocarbons. This is because the carbon atoms in saturated hydrocarbons are already bonded to the maximum number of hydrogen atoms, making them relatively stable. Unsaturated hydrocarbons, with multiple bonds, have weaker bonds that are more prone to breaking, allowing them to react more readily with other molecules. For example, ethane (C2H6), a saturated hydrocarbon, is relatively unreactive compared to ethene (C2H4), an unsaturated hydrocarbon with a double bond. The double bond in ethene is less stable and can be broken more easily to form new bonds.</p> Signup and view all the answers

<p>The general formula for an alkane with 'n' number of carbon atoms is CnH2n+2. This formula is based on the observation that each successive member of the alkane homologous series differs by a –CH2- unit. The first alkane, methane (CH4), has one carbon atom. The second alkane, ethane (C2H6), has two carbon atoms and is formed by adding a –CH2- unit to methane. The third alkane, propane (C3H8), has three carbon atoms and is formed by adding a –CH2- unit to ethane. This pattern continues for all members of the alkane series, leading to the general formula CnH2n+2.</p> Signup and view all the answers

<p>The molecular formula for the saturated hydrocarbon with seven carbon atoms is C7H16. This is because alkanes follow the general formula CnH2n+2, where 'n' represents the number of carbon atoms. For a hydrocarbon with seven carbon atoms, the formula becomes C7H(2*7)+2, which simplifies to C7H16.</p> Signup and view all the answers

<p>These compounds all belong to the homologous series of alcohols, which means they share the same functional group (OH) and differ only in the length of their carbon chain. The presence of the hydroxyl group (OH) determines the chemical properties of the alcohol series, overriding the influence of the carbon chain length. The carbon chain primarily influences the physical properties, such as boiling point, which gradually increases with a longer chain length. Therefore, while the carbon chains change, the chemical properties remain similar due to the presence of the same functional group, resulting in similar reactions and properties.</p> Signup and view all the answers

<p>The electron dot structure for butane (C4H10) would have four carbon atoms linked in a chain, with each carbon atom forming four bonds (either to hydrogen or other carbon atoms). Propane (C3H8) would have three carbon atoms in a chain. The difference lies in the number of carbon atoms and the corresponding number of hydrogen atoms. The additional carbon atom in butane contributes to its higher molecular weight and slightly different physical properties like boiling point. However, both butane and propane are saturated hydrocarbons with only single bonds, making them relatively unreactive compared to unsaturated compounds.</p> Signup and view all the answers

<p>Though benzene (C6H6) has only single bonds in its ring structure, it is considered unsaturated because its structure contains delocalized electrons. This delocalization means that the electrons in the ring structure are not fixed between two specific carbon atoms but rather spread out over the entire ring. This delocalization makes the ring more stable compared to a simple cyclic alkane with alternating single and double bonds. The presence of these delocalized electrons contributes to its reactivity, making it an unsaturated hydrocarbon.</p> Signup and view all the answers

<p>CnH2n</p> Signup and view all the answers

<p>14</p> Signup and view all the answers

<p>14</p> Signup and view all the answers

<p>Alcohol</p> Signup and view all the answers

<p>Propane</p> Signup and view all the answers

<p>Alkanes have the general formula CnH2n+2, alkenes have CnH2n, and alkynes have CnH2n-2. This shows a trend of decreasing hydrogen atoms compared to carbon atoms as you move from alkanes to alkynes. This is because alkanes have only single bonds, alkenes have one double bond, and alkynes have one triple bond.</p> Signup and view all the answers

<p>As molecular mass increases in a homologous series, physical properties like melting point, boiling point, and solubility change in a predictable manner. For example, the melting and boiling points increase due to stronger intermolecular forces caused by larger molecular size. Solubility in a particular solvent may decrease because of the increased nonpolar nature of larger molecules.</p> Signup and view all the answers

<p>Chemical properties are determined by the functional group present in the molecule. Since all members of a homologous series share the same functional group, they exhibit similar chemical reactions. The increase in molecular mass only affects the strength of intermolecular forces, not the reactivity determined by the functional group.</p> Signup and view all the answers

<p>Naming a carbon compound involves identifying the number of carbon atoms and then adding prefixes or suffixes to indicate the functional group and saturation. For example, a three-carbon chain with a ketone group would be named propanone. 'Propane' refers to the three-carbon chain, and 'one' indicates the ketone functional group (suffix). If the carbon chain is unsaturated, 'ane' is replaced with 'ene' or 'yne' depending on the type of unsaturation.</p> Signup and view all the answers

<p>Saturated hydrocarbons contain only single bonds between carbon atoms, like alkanes with the general formula CnH2n+2. Unsaturated hydrocarbons have at least one double or triple bond, like alkenes (CnH2n) with a double bond and alkynes (CnH2n-2) with a triple bond. Saturated hydrocarbons are typically less reactive than unsaturated hydrocarbons because they have fewer reactive sites.</p> Signup and view all the answers

<p>Unlike typical alkanes, cyclohexane forms a ring structure with six carbons. However, despite the cyclical structure, all carbon atoms in cyclohexane are connected by single bonds. This means it lacks any double or triple bonds, fulfilling the condition for a saturated hydrocarbon, even though its structure is not linear.</p> Signup and view all the answers

<p>A homologous series is generated by systematically increasing the number of carbon atoms in the main chain while maintaining the same functional group. For example, by adding one CH2 unit to the main chain of methanol (CH3OH), we obtain ethanol (C2H5OH), then propanol (C3H7OH), and so on. Key characteristics of a homologous series include similar chemical properties due to the same functional group and gradual changes in physical properties like melting and boiling points with increasing molecular mass.</p> Signup and view all the answers

<p>Carbon's ability to form four bonds allows it to create a vast array of structures, forming long chains, branched structures, rings, and various combinations with other atoms like hydrogen, oxygen, and nitrogen. This tetravalency of carbon is the foundation for the complexity and diversity of organic compounds, leading to the existence of millions of different organic molecules.</p> Signup and view all the answers

<p>Structural isomers are molecules with the same molecular formula but different arrangements of atoms. For example, butane (C4H10) has two isomers: n-butane and isobutane. They have identical molecular formulas but differ in the arrangement of carbon atoms. Structural isomerism is possible due to carbon's ability to form four bonds, allowing for branching in carbon chains.</p> Signup and view all the answers

<p>Alkanes have only single bonds (CnH2n+2), alkenes have one double bond (CnH2n), and alkynes have one triple bond (CnH2n-2). Alkenes and alkynes are more reactive than alkanes due to the presence of double or triple bonds. These bonds are inherently weaker and more susceptible to breaking, leading to a greater reactivity compared to the strong single bonds in alkanes.</p> Signup and view all the answers

<p>The formula CnH2n reveals that alkenes have double bonds between carbon atoms. Each carbon atom in the chain forms a double bond with another, leaving two remaining bonds to attach to hydrogen atoms. This implies that the molecule has fewer hydrogen atoms than a comparably sized alkane, indicating the presence of unsaturation.</p> Signup and view all the answers

<p>The boiling point would increase. As the carbon chain lengthens, the molecule's surface area and London dispersion forces increase, resulting in stronger intermolecular attractions that require more energy to overcome during vaporization.</p> Signup and view all the answers

<p>The functional group in alcohols is the hydroxyl group (-OH). While the presence of this group dictates the chemical behavior of alcohols, the reactivity of the hydroxyl group itself remains consistent regardless of the length of the carbon chain. Therefore, the chemical properties within the homologous series of alcohols remain similar.</p> Signup and view all the answers

<p>Butanone.</p> Signup and view all the answers

<p>Removing the final 'e' ensures that the name flows smoothly and avoids awkward pronunciation. For example, a three-carbon chain with a ketone group is named propanone instead of propaneone. Removing the 'e' creates a more aesthetically pleasing and pronounceable name.</p> Signup and view all the answers

<p>Saturated hydrocarbons contain only single bonds between carbon atoms, whereas unsaturated hydrocarbons contain at least one double or triple bond between carbon atoms. Methane (CH4) is a saturated hydrocarbon, while ethene (C2H4) is an unsaturated hydrocarbon.</p> Signup and view all the answers

<p>Butene.</p> Signup and view all the answers

<p>Hydrocarbons with four or more carbon atoms can have different arrangements of the carbon chain, leading to structural isomers. For example, butane (C4H10) can exist as two isomers: n-butane, with a straight chain of four carbon atoms, and isobutane, with a branched chain. The different arrangements of carbon atoms lead to different physical and chemical properties.</p> Signup and view all the answers

<p>The suffix '-yne' would be used to indicate the presence of a triple bond.</p> Signup and view all the answers

<p>As the carbon chain length increases, the melting and boiling points of compounds within a homologous series also increase. This is due to the growth of London dispersion forces, which are temporary attractions between molecules that become stronger with an increase in molecular size. These stronger intermolecular attractions require more energy to overcome, leading to higher melting and boiling points.</p> Signup and view all the answers

<p>Ant sting, as its main component is methanoic acid, the strongest acid listed.</p> Signup and view all the answers

<p>A solution is considered acidic if it has a higher concentration of hydrogen ions (H+). A solution is considered basic if it has a lower concentration of hydrogen ions (H+). A solution is considered neutral if the concentration of hydrogen ions (H+) and hydroxide ions (OH-) are equal.</p> Signup and view all the answers

<p>A strong acid is one that completely ionizes or breaks down into its ions in solution. A weak acid only partially ionizes in solution.</p> Signup and view all the answers

<p>Increasing the concentration of H+(aq) ions will decrease the pH of the solution.</p> Signup and view all the answers

<p>Maintaining the pH of soil is crucial for plant growth and nutrient availability.</p> Signup and view all the answers

<p>Quick lime (calcium oxide) is a base. When added to acidic soil, it reacts with the acids in the soil, neutralizing them and increasing the pH of the soil.</p> Signup and view all the answers

<p>Methanoic acid</p> Signup and view all the answers

<p>The dock plant contains compounds that can neutralize the methanoic acid in nettle stings.</p> Signup and view all the answers

<p>Lactic acid</p> Signup and view all the answers

<p>A salt is an ionic compound formed by the reaction of an acid and a base, where the hydrogen ion (H+) from the acid is replaced by a metal ion or ammonium ion (NH4+). An example is sodium chloride (NaCl), formed from the reaction of hydrochloric acid (HCl) and sodium hydroxide (NaOH).</p> Signup and view all the answers

<p>The dock plant leaf is traditionally used for a nettle sting as it is an acidic plant, helping to neutralize the basic methanoic acid in the nettle's sting.</p> Signup and view all the answers

<p>Acetic acid</p> Signup and view all the answers

<p>The pH of a solution is inversely proportional to the hydrogen ion concentration. A solution with a pH of 6 has a higher concentration of hydrogen ions than a solution with a pH of 8.</p> Signup and view all the answers

<p>A higher concentration of H+(aq) ions makes the solution more acidic, while a lower concentration makes it more basic.</p> Signup and view all the answers

<p>Basic solutions have a lower concentration of H+(aq) ions compared to their hydroxide (OH-) ions.</p> Signup and view all the answers

<p>A farmer would use these materials to neutralize acidic soil, making it more alkaline.</p> Signup and view all the answers

<p>Salts are formed when a base reacts with an acid, neutralizing each other to form a salt and water.</p> Signup and view all the answers

<p>Sodium chloride (NaCl) - table salt; Calcium carbonate (CaCO3) - chalk/ antacids; Potassium nitrate (KNO3) - fertilizer.</p> Signup and view all the answers

<p>Milk</p> Signup and view all the answers

<p>The dock plant is a traditional remedy for nettle stings due to its acidic nature, which neutralises the basic methanoic acid secreted by the nettle.</p> Signup and view all the answers

<p>Solution A has a lower pH, indicating a higher concentration of hydrogen ions (H+). A lower pH means the solution is more acidic. Solution B has a higher pH, indicating a lower concentration of hydrogen ions, making it more basic or alkaline.</p> Signup and view all the answers

<p>The higher the concentration of H+(aq) ions, the more acidic the solution. Conversely, the lower the concentration of H+(aq) ions, the more basic (alkaline) the solution.</p> Signup and view all the answers

<p>Basic solutions contain a lower concentration of H+(aq) ions compared to OH-(aq) ions. The presence of a higher concentration of OH- ions, which react with H+ ions, is the defining characteristic of a basic solution.</p> Signup and view all the answers

<p>Farmers treat soil with quicklime, slaked lime, or chalk to increase its pH, making it less acidic. These compounds are alkaline and react with acidic soil components to neutralize the acidity.</p> Signup and view all the answers

<p>The reaction between a strong acid and a strong base is a neutralization reaction. In this case, HCl reacts with NaOH producing salt (NaCl) and water (H2O). The salt is typically a neutral compound, while water is amphiprotic, meaning it can act as both an acid and a base.</p> Signup and view all the answers

<p>Salts are generally considered neutral because they are formed from the reaction of an acid and a base, where the hydrogen ions (H+) from the acid combine with the hydroxide ions (OH-) from the base to form water (H2O) and a salt. The salt formed does not typically contain excess H+ or OH- ions, resulting in a neutral pH.</p> Signup and view all the answers

<p>Acids typically release hydrogen ions (H+) when dissolved in water, making the solution more acidic, while bases release hydroxide ions (OH-) when dissolved in water, making the solution more alkaline or basic. Acids have a sour taste, while bases have a bitter taste. Acids turn blue litmus paper red, while bases turn red litmus paper blue.</p> Signup and view all the answers

<p>The salt formed from a strong acid and a strong base will be neutral. For example, NaCl (sodium chloride) formed from HCl (hydrochloric acid) and NaOH (sodium hydroxide) is neutral. If a strong acid reacts with a weak base, a slightly acidic salt is formed. For example, NH4Cl (ammonium chloride) formed from HCl and NH3 (ammonia) is slightly acidic. If a weak acid reacts with a strong base, a slightly basic salt is formed. For example, NaF (sodium fluoride) formed from HF (hydrofluoric acid) and NaOH is slightly basic.</p> Signup and view all the answers

<p>Neutralization is a chemical reaction that occurs when an acid and a base react to form salt and water. This process is used in everyday life for various purposes: Antacids use neutralizing agents to relieve acid indigestion. Farmers use lime to neutralize acidic soil. pH indicator solutions are used in swimming pools to maintain optimal pH levels.</p> Signup and view all the answers

<p>The pH of a solution is crucial for various applications because it affects chemical reactions, biological processes, and material properties. For example, in biological systems, like our bodies, maintaining a specific pH range is essential for proper enzyme function and overall health. The pH of soil influences plant growth; the pH of water affects aquatic organisms, and the pH of industrial processes can impact product quality and efficiency.</p> Signup and view all the answers

<p>pH is a measure of the acidity or alkalinity of a solution. It is a logarithmic scale that ranges from 0 to 14. A pH of 7 is considered neutral, a pH below 7 is acidic, and a pH above 7 is basic. The pH is inversely proportional to the concentration of hydrogen ions (H+) in a solution. Higher concentration of H+ ions results in lower pH (more acidic), while lower concentration of H+ ions leads to higher pH (more basic). For instance, a solution with a pH of 3 has a ten times higher concentration of H+ ions than a solution with a pH of 4.</p> Signup and view all the answers

<p>The nature of a solution is directly related to the concentration of hydrogen ions (H+). Acidic solutions have a higher concentration of H+ ions, making them more acidic. The presence of H+ ions makes acidic solutions sour, capable of reacting with bases to form salts and water, and can turn blue litmus paper red.</p> Signup and view all the answers

<p>Neutralization reactions occur when an acid and a base react with each other. The reaction results in the formation of a salt and water, and the solution becomes neutral. During the reaction, the hydrogen ions (H+) from the acid combine with the hydroxide ions (OH-) from the base to form water (H2O). For instance, when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH), sodium chloride (NaCl) and water (H2O) are formed: HCl + NaOH -&gt; NaCl + H2O.</p> Signup and view all the answers

<p>Many traditional remedies for insect stings rely on natural acids and bases. For example, rubbing dock plant leaves on a nettle sting is a traditional remedy because the dock plant contains oxalic acid, which neutralizes the methanoic acid in the nettle sting. The acidic nature of vinegar or lemon juice is used to neutralize the basic nature of an ant sting. These remedies work by neutralizing the acidic or basic nature of the sting, thus reducing its pain and inflammation.</p> Signup and view all the answers

<p>The pH scale is a logarithmic scale that ranges from 0 to 14, where 0 is the most acidic, 14 is the most basic, and 7 is neutral. A solution with a pH of 6 is acidic, meaning it has a higher concentration of hydrogen ions (H+). A solution with a pH of 8 is basic, meaning it has a lower concentration of H+ ions. Each whole number change in pH represents a tenfold change in the concentration of H+ ions.</p> Signup and view all the answers

<p>The pH of a solution can influence the solubility of certain substances. Acidic solutions (low pH) have a higher concentration of H+ ions, which can react with certain substances, promoting their solubility. For example, calcium carbonate (CaCO3), the main component of limestone, is more soluble in acidic solutions because the H+ ions react with carbonate ions (CO32-) to form bicarbonate ions (HCO3-) and water. Conversely, other substances like metal hydroxides are more soluble in basic solutions (high pH) due to the presence of OH- ions, which can react with metal cations to form soluble hydroxides.</p> Signup and view all the answers

<p>Maintaining a balanced pH level is crucial for the proper functioning of various biological systems. Slight deviations from the normal pH range can have significant consequences. For example, in human blood, the normal pH range is slightly basic (7.35-7.45). If blood pH drops below this range (acidosis), it can lead to breathing difficulties, fatigue, and confusion. Conversely, an increase in blood pH (alkalosis) can cause muscle spasms, seizures, and even death. Similarly, in the digestive system, the stomach maintains a highly acidic environment (pH 1-3) to aid in digestion. Deviations in stomach pH can lead to indigestion and other digestive disorders.</p> Signup and view all the answers

<p>Salts are essential compounds that play vital roles in everyday life. They are neutral ionic compounds formed by the reaction between an acid and a base. Salts are produced through neutralization reactions, where the hydrogen ions from the acid combine with the hydroxide ions from the base to form water, leaving behind the salt. Common examples of salts include table salt (NaCl), baking soda (NaHCO3), and Epsom salt (MgSO4·7H2O). Salts have diverse applications, including seasoning food, preserving food, making soap, and in various industrial processes.</p> Signup and view all the answers

<p>Acid rain is a form of precipitation that is more acidic than normal rainwater due to the presence of pollutants like sulfur dioxide (SO2) and nitrogen oxides (NOx) in the atmosphere. These pollutants are released primarily from burning fossil fuels in power plants and vehicles. In the atmosphere, SO2 and NOx react with water, oxygen, and other substances to form sulfuric acid (H2SO4) and nitric acid (HNO3), respectively. These acids then fall to the ground as acid rain. Acid rain can have devastating effects on ecosystems and human health. It can acidify lakes and streams, killing fish and other aquatic life. It can damage forests by dissolving nutrients in the soil and releasing toxic metals. It can also erode buildings and monuments, and contribute to respiratory problems and other health issues in humans.</p> Signup and view all the answers

<p>Acids and bases are two fundamental classes of chemical compounds with distinct properties. Acids have a sour taste, a pH less than 7, turn blue litmus paper red, and react with metals to produce hydrogen gas. Bases, on the other hand, have a bitter taste, a pH greater than 7, turn red litmus paper blue, and do not generally react with metals. Acids and bases can neutralize each other in a reaction that releases heat and forms salt and water.</p> Signup and view all the answers

<p>Indicators</p> Signup and view all the answers

<p>Less than 7</p> Signup and view all the answers

<p>7</p> Signup and view all the answers

<p>NaCl</p> Signup and view all the answers

<p>Rock salt</p> Signup and view all the answers

<p>7</p> Signup and view all the answers

<p>Less than 7</p> Signup and view all the answers

<p>Greater than 7</p> Signup and view all the answers

<p>Sodium chloride</p> Signup and view all the answers

<p>Salts formed from a strong acid and a weak base are acidic because the weak base's conjugate acid is stronger than the strong acid's conjugate base. This leads to an excess of hydrogen ions (H+) in the solution, resulting in a lower pH value, indicating acidity.</p> Signup and view all the answers

<p>The pH of a salt solution can be determined using pH paper or a pH meter. A pH value less than 7 indicates acidity, a pH value greater than 7 indicates basicity, and a pH value of 7 indicates neutrality.</p> Signup and view all the answers

<p>The Dandi March, led by Mahatma Gandhi, protested the British salt tax. Sodium chloride, a common salt used in food, was a symbol of resistance against the British rule and became a powerful tool in the Indian independence movement.</p> Signup and view all the answers

<p>Rock salt is a solid, crystalline form of sodium chloride found in deposits formed when ancient seas dried up. Sea salt is obtained by evaporating seawater, which contains various dissolved salts, primarily sodium chloride.</p> Signup and view all the answers

<p>The pH of a salt solution is determined by the relative strengths of the acid and base used to form it. A strong acid and strong base yield a neutral salt, a strong acid and weak base produce an acidic salt, and a strong base and weak acid result in a basic salt.</p> Signup and view all the answers

<p>To classify a salt, consider the strength of the acid and base from which it is formed. Strong acid + strong base = neutral salt; strong acid + weak base = acidic salt; strong base + weak acid = basic salt.</p> Signup and view all the answers

<p>The pH of a salt solution is inversely proportional to the concentration of hydrogen ions (H+). A higher concentration of H+ results in a lower pH, indicating acidity. A lower concentration of H+ leads to a higher pH, indicating basicity.</p> Signup and view all the answers

<p>A salt family consists of salts that share the same cation (positive ion) or anion (negative ion). For example, NaCl (sodium chloride) and Na2SO4 (sodium sulfate) belong to the sodium salt family, as they both contain the sodium ion (Na+).</p> Signup and view all the answers

<p>A salt's solubility affects its ability to influence pH because only dissolved ions can interact with water molecules, contributing to acidity or basicity. Insoluble salts have minimal impact on pH due to their limited interaction with water.</p> Signup and view all the answers

<p>Hydrolysis of salt ions can affect the pH of the solution. When a salt ion reacts with water, it can produce either H+ or OH-. If it produces H+, the solution becomes acidic, and if it produces OH-, the solution becomes basic.</p> Signup and view all the answers

<p>Salts formed from a strong acid and a strong base are neutral because the strong acid and strong base completely neutralize each other, resulting in a solution with a pH of 7. Salts formed from a strong acid and a weak base are acidic because the strong acid donates more hydrogen ions (H+) to the solution, lowering the pH below 7. A weak base can't completely neutralize all the hydrogen ions released by the strong acid.</p> Signup and view all the answers

<p>If the pH of a salt solution is less than 7, it indicates the salt was formed from a strong acid and a weak base. If the pH is greater than 7, it suggests the salt was formed from a strong base and a weak acid. A pH of 7 indicates a neutral salt formed from a strong acid and a strong base. For example, if a salt solution has a pH of 3, it suggests that the salt was formed from a strong acid like hydrochloric acid (HCl) and a weak base like ammonia (NH3).</p> Signup and view all the answers

<p>Salts can be classified into families based on sharing the same positive or negative ions (radicals). For example, NaCl and Na2SO4 both contain the sodium ion (Na+) and belong to the sodium salt family. Similarly, NaCl and KCl share the chloride ion (Cl-) and belong to the chloride salt family. This classification helps organize and understand the properties of different salts.</p> Signup and view all the answers

<p>Seawater contains various salts, including sodium chloride. Obtaining table salt from seawater involves evaporation. The seawater is heated to evaporate the water, leaving behind concentrated salt. The salt is then purified and processed. Rock salt is obtained by mining solid salt deposits, typically formed when ancient seas dried up. The mined rock salt needs to be crushed, purified, and processed for table salt production.</p> Signup and view all the answers

<p>Adding a strong acid to a salt solution will generally decrease the pH, making the solution more acidic. This is because the acid donates excess hydrogen ions (H+). For instance, adding hydrochloric acid to a sodium chloride solution will make it more acidic. Adding a strong base to a salt solution will generally increase the pH, making the solution more basic. The base neutralizes hydrogen ions in the solution. Adding sodium hydroxide to a sodium chloride solution would make it more basic.</p> Signup and view all the answers

<p>Salt formation involves a neutralization reaction because it results from the reaction of an acid and a base, with the acid's hydrogen ions (H+) reacting with the base's hydroxide ions (OH-) to form water. For example, when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH), they neutralize each other to form sodium chloride (NaCl) and water (H2O). The salt formed is the product of the neutralization reaction.</p> Signup and view all the answers

<p>Sodium chloride is essential for human health as it plays a crucial role in maintaining fluid balance, nerve impulses, and muscle contractions. It is also important for various industries, including food preservation, chemical production, and road de-icing. Salt is used in food as a flavor enhancer and a preservative, while it is a key ingredient in the manufacture of plastics, paper, and other chemicals.</p> Signup and view all the answers

<p>Sodium carbonate (Na2CO3) is a strong base, while sodium hydrogencarbonate (NaHCO3) is a weak base. This difference is due to the presence of an additional hydrogen ion in NaHCO3. Sodium carbonate is used in glass production, detergents, and paper manufacturing, while sodium hydrogencarbonate is used as a leavening agent in baking, an antacid, and a cleaning agent. The different properties arise from their differing basicity.</p> Signup and view all the answers

<p>If a salt solution has a pH less than 7, it indicates the acid component of the salt was stronger than the base component. If the pH is greater than 7, it means the base component was stronger. For example, a salt formed from a strong acid and a weak base will have a lower pH due to the excess hydrogen ions (H+) from the stronger acid.</p> Signup and view all the answers

<p>Sodium chloride (table salt) has been historically significant for its role in food preservation, flavoring, and trade. In ancient times, salt was used as a form of currency and was a valuable commodity. The Dandi Salt March led by Mahatma Gandhi highlighted the importance of salt in India's struggle for independence. Salt remains a critical ingredient in various culinary traditions and cultural practices worldwide.</p> Signup and view all the answers

<p>The chlor-alkali process.</p> Signup and view all the answers

<p>Sodium hydroxide, chlorine gas, and hydrogen gas.</p> Signup and view all the answers

<p>By reacting chlorine gas with dry slaked lime (Ca(OH)2).</p> Signup and view all the answers

<p>Ca(OCl)2.</p> Signup and view all the answers

<p>It acts as the source of sodium ions in the brine solution for electrolysis.</p> Signup and view all the answers

<p>Chlorine gas (Cl2).</p> Signup and view all the answers

<p>Because it produces chlorine (chlor) and sodium hydroxide (alkali).</p> Signup and view all the answers

<p>Hydrogen gas (H2).</p> Signup and view all the answers

<p>It is used in the manufacture of various chemicals, detergents, and food processing.</p> Signup and view all the answers

<p>CaOCl2</p> Signup and view all the answers

<p>Sodium hydroxide is produced by the electrolysis of brine (aqueous solution of sodium chloride) in a process called the chlor-alkali process. Electricity decomposes the brine, forming sodium hydroxide at the cathode, chlorine gas at the anode, and hydrogen gas at the cathode.</p> Signup and view all the answers

<p>Sodium hydroxide (NaOH), chlorine gas (Cl2), and hydrogen gas (H2).</p> Signup and view all the answers

<p>The chlor-alkali process yields three essential industrial products: sodium hydroxide, chlorine gas, and hydrogen gas. These products are used in various industries, making the process crucial for manufacturing.</p> Signup and view all the answers

<p>Ca(OH)2 + Cl2 → CaOCl2 + H2O</p> Signup and view all the answers

<p>Common salt (sodium chloride) serves as a key raw material for manufacturing various chemicals, including sodium hydroxide, baking soda, washing soda, and bleaching powder, contributing to several industrial applications.</p> Signup and view all the answers

<p>The process is called the chlor-alkali process.</p> Signup and view all the answers

<p>Bleaching powder is produced by reacting chlorine gas with dry slaked lime [Ca(OH)2]. The reaction results in the formation of CaOCl2 (bleaching powder) and water (H2O).</p> Signup and view all the answers

<p>The chlor-alkali process, which produces sodium hydroxide from brine, is a vital industrial process because sodium hydroxide is used extensively in various industries. Its applications range from manufacturing soap, paper, and textiles to the production of other chemicals.</p> Signup and view all the answers

<p>The chlor-alkali process involves passing electricity through an aqueous solution of sodium chloride (brine). This leads to the decomposition of sodium chloride into its constituent ions: sodium ions (Na+) and chloride ions (Cl-). At the cathode, the reduction of water molecules occurs, producing hydroxide ions (OH-) and hydrogen gas (H2). At the anode, chloride ions are oxidized, liberating chlorine gas (Cl2). The overall reaction can be represented as:</p> <p>2NaCl(aq) + 2H2O(l) → 2NaOH(aq) + Cl2(g) + H2(g)</p> <p>The process is termed 'chlor-alkali' because the primary products are chlorine ('chlor') and sodium hydroxide ('alkali'). Sodium hydroxide is also known as caustic soda.</p> Signup and view all the answers

<p>Bleaching powder is produced by reacting chlorine gas with dry slaked lime [Ca(OH)2]. The reaction can be represented as:</p> <p>Ca(OH)2 + Cl2 → CaOCl2 + H2O</p> <p>The chlorine gas reacts with calcium hydroxide, forming calcium hypochlorite (CaOCl2). This reaction produces bleaching powder. The simplified formula CaOCl2 represents the main component of bleaching powder, but the actual composition is more complex, often including calcium chloride (CaCl2). This is because the reaction is not always stoichiometric, and other species, like basic calcium hypochlorite, can be present.</p> Signup and view all the answers

<p>The chlor-alkali process is a fundamental source of essential chemicals, including chlorine gas, sodium hydroxide, and hydrogen gas. These products are the building blocks for various everyday materials. For example, sodium hydroxide is used extensively in soap and detergent production, the manufacture of paper, and in the refining of petroleum products. Chlorine is crucial for the production of PVC plastic, disinfectants, and bleaching agents. Hydrogen gas is used in the production of ammonia, which is then used for fertilizers and other products.</p> Signup and view all the answers