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Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 MATTER, Atomic Structure, Periodic Table, Freezing point Electronic Configuration The temperature at which a liquid change into a...

Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 MATTER, Atomic Structure, Periodic Table, Freezing point Electronic Configuration The temperature at which a liquid change into a solid. Boiling point Chemistry The boiling point of an element or compound is the study of matter, its properties, the changes that means the temperature at which the liquid form of matter undergoes, & the energy associated with an element or compound is at equilibrium with the these changes gaseous form. the boiling point of water is 100 degrees Celsius. Matter Is anything that has mass and occupies space Melting point Composition The temperatures at which the solid form of the element or compound is at equilibrium with the the types and amounts of simpler substances that liquid form. make up a sample of matter Basically the range at which the solid changes its Properties state into a liquid. the characteristics that give each substance a unique The melting point of water is 0 degrees Celsius identity Compound − Physical Properties- those which the A substance made of two or more elements substance shows by itself without chemically combined in a set ratio. interacting with another substance such as – Water and salt are 2 examples of compounds. color, melting point, boiling point, density − Chemical Properties- those which the substance shows as it interacts with, or Two basic types of properties of matter: Physical properties and Chemical properties: transforms into, other substances such as flammability, corrosiveness Physical Properties Energy is the capacity to do work. Physical properties are used to identify, describe and Potential Energy classify matter. Energy due to the position of the object or – Characteristic of a substance that can be observed energy from a chemical reaction (using your senses) without changing the substance Kinetic Energy into something else. Energy due to the motion of the object Chemical Properties Matter Chemical properties are characteristics involved Anything that has mass and takes up space when a substance interacts with another substance Mass to change its chemical make-up. A measure of how much matter is in an object. States of Matter Volume − There are different “states” of matter. Or also The amount of space that matter occupies. known as phases (a physical state of matter). Density − Elements and compounds can move from one The measurement of how much mass of a substance phase to another phase when special physical is contained in a given volume. forces are present. Density = Mass Solid Volume liquid Gas Mikaella Nagano 1  Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Chemical Property A property of matter that describes a substance based on its ability to change into a new substance with different properties Can be observed with your senses. Combustibility Flammability Reactivity – Acids – Bases Physical Properties – Oxidation A property of matter that can be observed or Physical Change measured without changing the identity of the A change that affects one or more physical matter. properties of a substance. Physical properties identify matter. Do Not form new substances. – Examples include but are not limited to: Can often be Undone Density – Example Butter on counter can be placed back in Malleability refrigerator. Ductility – Change of State Solubility Solid to Liquid State Liquid to Gas Thermal Conductivity Chemical Change Density A change that occurs when one or more substances are − Amount of mass in a given volume changed into entirely new substances with different − A substance is always the same at a given properties. pressure and temperature regardless of the Can Not change back under normal conditions size of the sample of the substance. (some can − The density of one substance is usually be changed back by other chemical means) different from that of another substance Common Examples: − D=m/v – Reactivity – Oxidation (rust) on a bicycle Malleability – pH (Acid / Base) – Effervescent tablets – Flammability – Burnt wood The ability to be pounded into thin sheets – Combustibility – Fireworks Ductility Classification of Matter The ability to be drawn or pulled into a wire Substance Solubility is a form of matter that has definite composition and distinct properties. The ability to dissolve in another substance Substances can be classified as either elements or Thermal Conductivity compounds The ability to transfer thermal energy from one area to another. Mikaella Nagano 2  Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Mixture is a physical combination of two or more substances can be separated by physical means into its components without changing the identities of the components. − homogeneous mixture is uniform throughout. − heterogeneous mixture is not uniform throughout. Components of Matter Element - the simplest type of substance with unique physical and chemical properties. An element consists of only one type of atom. It cannot be broken down into any simpler substances by physical or chemical means Molecule - a structure that consists of two or more atoms that are chemically bound together and thus behaves as an independent unit. Compound - a substance composed of two or more elements which are chemically combined. Mixture - a group of two or more elements and/or compounds that are physically intermingled. Isotopes Isotopes are atoms of an element with the same number of protons, but a different number of neutrons. Isotopes have the same atomic number, but a different mass number Mikaella Nagano 3 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 The Modern Periodic table substance. The empirical formula for hydrogen peroxide is HO. Dmitri Ivanovich Mendeleev (1834-1907) The molecular formula for hydrogen peroxide is Russian chemist H2O2. Created his own version of periodic table to The structural formula for hydrogen peroxide is H-O- correct some properties already known. O-H. Arranged the elements acc to atomic Naming Binary Ionic Compounds number and not mass For all ionic compounds, the name and formula list the cation first and the anion Physical Properties of Metals second Good conductors of electricity and heat. The name of the cation is the same as the Malleable (can be hammered into sheets). name of the metal. Many metal names end Ductile (can be drawn into wires). in -ium Shinny at room temperature The anion is named by adding the suffix -ide Except Mercury to the root of the nonmetal name Compounds: Introduction to Bonding Elements Combine in two general ways: A. Transferring electrons from one element to another to form ionic compounds B. Sharing electrons between atoms of different elements to form covalent compounds These processes generate chemical bonds, the forces that holds the atoms together in a compound. Molecule – the basic unit of a molecular element or covalent compound, consisting of two or more PROBLEM: Name the ionic compound formed from atoms bonded by the sharing of electrons. each of the following pairs of elements: Most covalent substances consist of molecules. SOLUTION: Ion – a single atom or covalently bonded group of PLAN: Use the periodic table to decide which atoms that has an element is the metal and overall electrical charge. which the nonmetal. The metal (cation) is named There are no molecules in an ionic compound. first and the suffix –ide is added to the root of the non-metal name. Types of Chemical Formulas An empirical formula indicates the relative number (a) magnesium and nitrogen- magnesium nitride of atoms of each element in the compound. It is the (b) iodine and cadmium- cadmium iodide simplest type of formula. (c) strontium and fluorine- strontium fluoride A molecular formula shows the actual number of (d) sulfur and cesium- cesium sulfide atoms of each element in a molecule of the compound. A structural formula shows the number of atoms and the bonds between them, that is, the relative placement and connections of atoms in the molecule. A chemical formula is comprised of element symbols and numerical subscripts that show the type and number of each atom present in the smallest unit of the Mikaella Nagano 4 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Naming Binary Covalent Compounds A binary covalent compound is typically formed by the combination of two non-metals. Some of these compounds are very common and have trivial names, eg., H2O is water. For a binary covalent compound, the element with the lower group number in the periodic table is first in the name and formula. Its name remains unchanged. The element that is second is named using the root with the suffix –ide. Numerical prefixes indicate the number of atoms of each element present. Naming Acids 1) Binary acid solutions form when certain gaseous compounds dissolve in water. For example, when gaseous hydrogen chloride (HCl) dissolves in water, it forms a solution called hydrochloric acid. Prefix hydro- + anion nonmetal root + suffix -ic + the word acid - hydro + chlor + ic + acid hydrochloric acid 2) Oxoacid names are similar to those of the oxoanions, except for two suffix changes: -ate in the anion becomes –ic in the acid -ite in the anion becomes –ous in the acid The oxoanion prefixes hypo- and per- are retained. Thus, BrO4– is perbromate, and HBrO4 is perbromic acid; IO2– is iodite, and HIO2 is iodous acid Mikaella Nagano 5 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Classifications, Chemical Formulas , Naming and Writing formulas & Balancing of Equation COMPOUNDS IONIC COMPOUNDS MOLECULAR COMPOUNDS IONIC COMPOUNDS Referred to as salt Ionic compounds are formed from the attraction of charged atoms called IONS – are electrically charged atoms either positive or negative. Naming Straight-Chain Alkanes Nomenclature-It is a system of naming. To Hydrocarbons are compounds that contain only distinguish one chemical entity from carbon and hydrogen atoms. another, unique names are assigned to all elements, Alkanes are the simplest type of ions and compounds. hydrocarbon. NAMING IONIC COMPOUNDS Alkanes are named using a root name Ionic compound nomenclature or naming is based followed by the on the names of the component ions. In all cases, suffix –ane ionic compound naming gives the positively charged cation first, followed by the negatively charged anion. IONS CAN BE... MONATOMIC – consists of a single atom POLYATOMIC - are anions that contains oxygen attached to some other element, usually a non-metal. These polyatomic ions are called oxyanions. OXOANIONS – combination of oxygen with a non- metal although some contains metal. USING -ite AND -ate Some polyatomic anions contains oxygen. These anions are called oxyanions. When an element forms two oxyanions, the one with less oxygen is given a name ending in –ite and the one with more oxygen are given a name that ends in –ate NO2 –Nitrite NO3 - Nitrate SING HYPO- AND PER- In this case where there is a series of four oxyanions, the –hypo and per- prefixes indicates less oxygen and more oxygen respectively. CIO –Hypochlorite CIO2 – Chlorite Mikaella Nagano 6 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 IONIC COMPOUND CONTAINING BI- AND DI- HYDROGEN Polyatomic anions sometimes gain one or more H+ ions to form anions of a lower charge. These ions are named by adding the word hydrogen or dihydrogen in front of the name of the anion. It is still PREFIXES AND MOLECULAR common to see and use the older naming COMPOUND NAMES convention in which the prefix bi- is used to indicate the addition of a single hydrogen ion. HCO3 – Hydrogen carbonate or bicarbonate HSO4 – Hydrogen sulfate or bisulfate Classifications, Chemical Formulas , Naming and Writing formulas & Balancing of Equation STOCK SYSTEM The specific systematic method used to naming ionic compounds is called STOCK SYSTEM. It uses roman numerals in parenthesis after the name of the metal to indicate the charges Examples... ROMAN NUMERALS IN IONIC COMPOUND SO2 - sulfur dioxide NAMES SF6 – sulfur hexafluoride CCl4 – carbon tetrachloride A roman numeral in parentheses, followed by the NI3 - Nitrogen triiodide name of the element, is used for elements that can form more than one positive ion. There is no space between the element name and parenthesis. This notation is usually seen with metals since they commonly display more than one oxidation state or valence. Fe2 Iron(II) NAMING IONIC COMPOUNDS USING -OUS AND -IC Although roman numerals are used to denote the ionic charge of cations , it is still common to see and use the endings –ous and –ic. These endings are added to the Latin name of the element (e.g., stannous/stannic for tin) to represent the ions with lesser or greater charge, repectively. The roman numeral naming convention has wider appeal because many ions have more than two valences. Fe2+ Ferrous Fe3+ Ferric Mikaella Nagano 7 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Chemical Formulas TYPES OF CHEMICAL FORMULAS Molecular Formula – this formula uses the actual numbers of moles of each element. EX. Hydrogen peroxide: H2O2 Empirical Formula – simplest chemical formula. EX. Hydrogen peroxide: HO Structural Formula – it shows the number of atoms by means of showing the bonds between atoms. EX. Hydrogen peroxide: H-O-O-H Nature of Chemical Reaction A chemical reaction is a process that leads to the Types of Chemical Reactions transformation of one set of chemical 1. Synthesis Reaction (Combination Reaction) - In a substances to another. synthesis reaction, two or more substances combine Chemical reactions are usually characterized by a to form a new compound. This type of reaction is chemical change, from substances that are initially represented by the following equation. involved in a chemical reaction are called reactants or reagents. The reactant in a chemical reaction change into one or more new substance/s called product. Example: Reactants Products Iron + Oxygen Iron (III) oxide Hydrogen peroxide water + oxygen Classically, chemical reactions encompass changes that strictly involve the motion of electrons in the forming and breaking of chemical bonds between atoms, and can often be described by a chemical 2. Decomposition: this reaction is the opposite equation. of a synthesis reaction - a complex molecule breaks down to make simpler ones. These 1. Write the skeleton equation. reactions come in the general form: NaBr + Cl2 NaCl + Br2 AB ---> A + B 2. Count the atoms of each element. Reactants Products Example: electrolysis of water to make oxygen Na 1 Na 1 and hydrogen gas: Br 1 Br 2 2 H2O ---> 2 H2 + O2 Cl 2 Cl 1 3. Combustion Reaction - a substance combines with oxygen, releasing a large amount of energy in the form of light and heat. - For organic compounds - hydrocarbons, the products of the combustion reaction are carbon dioxide and water. Mikaella Nagano 8 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 4. Single displacement: This is when one One example of an acid-base reaction is the reaction element trades places with another element in of hydrobromic acid (HBr) with sodium hydroxide: HBr + NaOH ---> NaBr + H2O a compound. A + BC AC + B GAS LAW Kinetic Molecular Theory(KMT) The summary of the KMT postulates is as follows: Gases are composed of extremely minute particles, separated by wide spaces, called 5. Double displacement: This is when the anions molecules. and cations of two different molecules switch Molecules are in rapid random motion travelling places, forming two entirely different in straight path colliding with one another and compounds. against the wall of the container exerting pressure. AB + CD AD + CB Quantities that Influence the Nature and Behavior of Gases: Pressure (P) – force exerted by a gas per unit area Standard Pressure: 1atm (atmosphere) = 760 mmHg Temperature (T) – average kinetic energy of gas particles 5. Double displacement: This is when the anions and Standard Temperature: 273 K = 0°C cations of two different molecules switch places, forming two entirely different compounds. Gas Pressure and its Measurement AB + CD AD + CB Pressure = force/area example of a double displacement reaction is the Atmospheric pressure arises from the force exerted reaction of lead (II) nitrate with potassium iodide to by atmospheric gases on the earth’s surface. form lead (II) iodide and potassium nitrate: Atmospheric pressure decreases with altitude. Volume (V) – space occupied by gas particles 1 mol of gas = 22.4 L Number of Particles (n) – expressed in mole 1 mol of gas = 6.02 x 1023 particles Acid-base: This is a special kind of double Molecular Mass (m) displacement reaction that takes place when an acid 1 mol of gas = molecular mass (g and base react with each other. The H+ion in the acid reacts with the OH- ion in the base, causing the formation of water. Generally, the product of this reaction is some ionic salt and water: HA + BOH ---> H2O + BA Mikaella Nagano 9 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Mathematically P1V1 = P2V2 k = T and n Where P1 = initial pressure V1 = initial volume P2 = final pressure V2= final volume K = constant Charles’ Law: Volume-Temperature Relationship by French physicist Jacques Alexandre Charles in 1787. The kinetic energy of gas particles increases as temperature increases; the Kelvin temperature and volume of a gas are directly related with no change in pressure and amount of gas. The Gas Laws − At constant pressure, the volume occupied The gas laws describe the physical behavior of by a fixed amount of gas is directly gases in terms of 4 variables: proportional to its absolute (Kelvin) – pressure (P) temperature – temperature (T) – volume (V) – amount (number of moles, n) An ideal gas is a gas that exhibits linear relationships among these variables. No ideal gas actually exists, but most simple gases behave nearly ideally at ordinary temperatures and pressures. Boyle’s Law: Pressure-Volume Relationship by English chemist Robert Boyle in 1662. As volume becomes smaller, more collisions occur and the air pressure increases; pressure and volume are directly related at constant temperature Gay-Lussac’s Law: and amount of gas Pressure-Temperature Relationship by - At constant temperature, the volume occupied by French a fixed amount of gas is inversely proportional to the scientist Joseph Louis Gay-Lussac in 1808. external pressure. If the gas is heated, its pressure will increase, with constant volume and number of moles, the pressure of a gas is directly related to its Kelvin temperature Combined Gas Law: Used to solve for changes in pressure, volume and temperature of a gas Mikaella Nagano 10 Organic and Inorganic Chemirstry Lecture – 2nd Year – Chem111 Avogadro’s Law: Volume-Mole Relationship by Italian scientist Amadeo Avogadro in 1811 The volume of the gas is directly related to the number of moles at constant temperature and pressure. Ideal Gas Law Boyle’s Law, Charles’ Law and Avogadro’s Law were combined where the variables pressure, volume, temperature and amount of gas equated to a single constant R or the universal gas constant. Dalton’s Law of Partial Pressure by English chemist John Dalton in 1801. The total pressure exerted by a mixture of non-reacting gases is the sum of the partial pressures exerted by each gas. Graham’s Law of Diffusion: by Scottish chemist Thomas Graham in 1833. Lighter molecules with the same kinetic energy escape more rapidly than heavier ones; the rate of diffusion of gases and the square roots of their molecular masses are inversely related at constant temperature and pressure. − Effusion is the process by which a gas escapes through a small hole in its container into an evacuated space. − Graham’s law of effusion states that the rate of effusion of a gas is inversely proportional to the square root of its molar mass. − A lighter gas moves more quickly and therefore has a higher rate of effusion than a heavier gas at the same T. Mikaella Nagano 11