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Question Choices Answer Explanation Rutherford's model, also known as the nuclear...

Question Choices Answer Explanation Rutherford's model, also known as the nuclear model, A. proton and neutron proposed that atoms have a dense, positively charged 1. Based on Rutherford’s model of an atom, B. neutron and electron nucleus at their center. This nucleus contains protons, which subatomic particle is present in the A. proton and neutron C. proton and electron positively charged particles, and neutrons, neutral particles. nucleus of an atom? D. proton only Electrons, negatively charged particles, orbit the nucleus. Erwin Schrödinger's contribution to atomic theory was the development of the Quantum Mechanical Model. This model A. Nuclear Model 2. Among the various atomic models uses complex mathematical equations to describe the B. Planetary Model D. Quantum Mechanical developed throughout history, which specific behavior of electrons in atoms, emphasizing their wave-like C. Raisin-bread Model Model model was proposed by Erwin Schrödinger? nature and probability of location. The model replaced the D. Quantum Mechanical Model Bohr model's fixed orbits with probability regions called orbitals. A. Electrons move in fixed, circular orbits. The Quantum Mechanical Model departs from the idea of B. Electrons remain stationary fixed orbits. It describes electrons as existing in regions of 3. Which of the following is a key feature of the in the nucleus. D. Electrons exist in probability, called orbitals, around the nucleus. This means Quantum Mechanical Model regarding C. Electrons can be located probability regions called the we cannot know an electron's exact location at any given electron positions? precisely at any moment. electron cloud. time, only the likelihood of finding it in a specific D. Electrons exist in probability area. regions called the electron cloud. The correct designation for a sublevel follows the format "nℓ", where "n" is the principal quantum number (energy level) and A. 1p5 "ℓ" is the azimuthal quantum number (sublevel type). The "p" 4. Which of the following correctly identifies B. 3f9 sublevel can hold a maximum of 6 electrons. The other the designation of sublevels within the atomic C. 2p6 C. 2p6 options are incorrect: structure? D. 3d11 - 1p5: "p" sublevel cannot exist at the first energy level (n=1). - 3f9: "f" sublevel can hold a maximum of 14 electrons. - 3d11: "d" sublevel can hold a maximum of 10 electrons. Question Choices Answer Explanation 5. Consider an atom that absorbs energy and A. 3p to 3s When an electron transitions from a higher energy level to a then undergoes electron transitions. Which of B. 3p to 4p lower energy level, it releases energy in the form of light. This A. 3p to 3s these transitions would lead to the emission of C. 2s to 2p is called emission. The other options represent transitions to energy? D. 1s to 2s higher energy levels, which require energy absorption. A. 6 The first energy level (n=1) can hold a maximum of 2 6. If the first and second energy levels of an B. 8 electrons (1s²). The second energy level (n=2) can hold a atom are full, what is the total number of C. 10 C. 10 maximum of 8 electrons (2s² 2p⁶). Therefore, a full first and electrons in the atom? D. 18 second energy level would contain 2 + 8 = 10 electrons. In an excited state, an electron can temporarily occupy a higher energy level. Option D shows an electron from the 2p sublevel of Neon (Ne) moving to the 3s sublevel. The other 7. Imagine you are studying an atom that has A. H: 1d1 options are incorrect: absorbed energy, causing one of its electrons B. He : 1s² - H: 1d¹: Hydrogen (H) only has one electron, and the "d" to move to a higher energy level. Which of the D. Ne: 1s² 2s² 2p⁵ 3s¹ C. Na: 1s² 2s² 2p⁶ 3d¹ sublevel is not available at the first energy level. following configurations is possible for the D. Ne: 1s² 2s² 2p⁵ 3s¹ - He : 1s²: Helium (He) has a full first energy level and cannot electron in this excited state? be excited to a higher level. - Na: 1s² 2s² 2p⁶ 3d¹: Sodium (Na) does not have a 3d sublevel in its ground state. 8. The different colors seen in a firework A. Barium Strontium is the element responsible for the green color in display are due to the ignition of different B. Calcium fireworks. The excited electrons in strontium atoms emit light D. Strontium elements. Which element is responsible for C. Sodium in the green region of the visible spectrum when they return the green color in a fireworks display? D. Strontium to their ground state. Ionic compounds typically have high melting points because 9. John is testing two compounds. One has a A. Ionic bond the electrostatic attraction between oppositely charged ions high melting point and conducts electricity B. Metallic bond A. Ionic bond is strong. They also conduct electricity when dissolved in when dissolved in water. What type of bond C. Polar Covalent bond water because the ions become free to move and carry does this compound likely have? D. Nonpolar covalent bond charge. Question Choices Answer Explanation Similar to the previous question, ionic compounds exhibit 10. A certain compound is hard, has a high A. Ionic bond these properties. The strong electrostatic forces between melting point, and does not conduct electricity B. Metallic bond ions make them hard and require high temperatures to break A. Ionic bond in its solid form. What type of bond does it C. Polar covalent bond apart (high melting point). In their solid form, ions are fixed in likely have? D. Nonpolar covalent bond a lattice structure, preventing them from conducting electricity. 11. When choosing materials for electrical A. Ionic bond Metals are excellent conductors of electricity and heat due to wiring, which type of bond should you consider B. Metallic bond the presence of delocalized electrons. These electrons can B. Metallic bond for the highest electrical and thermal C. Polar covalent bond move freely throughout the metallic lattice, allowing for easy conductivity? D. Nonpolar covalent bond transfer of charge and energy. Water (H₂O) has a polar covalent bond. The oxygen atom is 12. While preparing a science project on water, more electronegative than the hydrogen atoms, resulting in A. Ionic bond you learn that water has unique properties, an uneven sharing of electrons and a partial negative charge B. Metallic bond including its ability to dissolve many C. Polar covalent bond on the oxygen and partial positive charges on the hydrogens. C. Polar covalent bond substances. What type of bond primarily This polarity allows water to form hydrogen bonds with other D. Nonpolar covalent bond contributes to water's properties? polar molecules, contributing to its high boiling point, surface tension, and ability to dissolve many substances. Nitrogen (N₂) is a diatomic molecule, meaning it consists of A. 1 13. Nitrogen (N) belongs to family 5A, and it is two nitrogen atoms bonded together. Each nitrogen atom has B. 2 diatomic. How many nonpolar covalent bonds B. 2 5 valence electrons, and they share three electrons each to C. 3 are present in an N₂ molecule? form a triple bond. This triple bond consists of three pairs of D. 4 shared electrons, resulting in two nonpolar covalent bonds. 14. In a chemistry lab, you have four A. salt substances: sodium chloride (salt), paraffin Ionic compounds like sodium chloride (salt) have strong B. table sugar wax (candle wax), sucrose (table sugar), and A. salt electrostatic attractions between ions, requiring significant C. paraffin wax lead wire. Which of the following will have the energy to break these bonds and melt the substance. D. lead wire highest melting temperature? Question Choices Answer Explanation A. The bond in Br₂ is metallic, Bromine (Br₂) is a diatomic molecule formed by the sharing of 15. Imagine you are observing two different while the bond in MgF₂ is ionic. electrons between two bromine atoms, creating a covalent compounds in a chemistry lab: bromine gas B. The bond in Br₂ is ionic, while bond. Magnesium fluoride (MgF₂) is formed by the transfer of (Br₂) and magnesium fluoride (MgF₂). As you the bond in MgF₂ is covalent. C. The bond in Br₂ is covalent, electrons from magnesium (Mg) to fluorine (F), resulting in analyze their molecular structures, how does C. The bond in Br₂ is covalent, while the bond in MgF₂ is ionic. an ionic bond where magnesium becomes a positively the bonding in Br₂ differ from the bonding in while the bond in MgF₂ is ionic. charged cation (Mg²⁺) and fluorine becomes a negatively MgF₂? D. There is no difference in charged anion (F⁻). bonding between the two. A. Anion 16. David sees an atom lose an electron and B. Cation An atom that loses an electron becomes positively charged become positively charged. What is this ion B. Cation C. Neutron and is called a cation. now called? D. Neutral atom A. It gains a proton. B. It loses an electron. Potassium (K) is a metal and tends to lose an electron to 17. When potassium forms an ion, what C. It shares electrons equally. B. It loses an electron. achieve a stable electron configuration, forming a positively happens to its atomic structure? D. It becomes negatively charged ion (K⁺). charged. A. Li and Si Lithium (Li) is an alkali metal and readily loses an electron to 18. Which two elements among the following B. Si and F become Li⁺. Fluorine (F) is a halogen and readily gains an D. Li and F are most likely to form an ionic bond? C. Ne and Si electron to become F⁻. The strong electrostatic attraction D. Li and F between these oppositely charged ions forms an ionic bond. A. Both atoms lose protons B. Both atoms gain neutrons Sodium (Na) is a metal and loses an electron to become Na⁺. 19. You dissolve salt in water, and the solution C. Sodium gains an electron, D. Sodium loses an electron, Chlorine (Cl) is a nonmetal and gains an electron to become conducts electricity. How do the ions in the and chlorine loses an electron and chlorine gains an electron Cl⁻. The electrostatic attraction between these oppositely salt form? D. Sodium loses an electron, charged ions forms ionic bonds in table salt (NaCl). and chlorine gains an electron Question Choices Answer Explanation A. They gain protons to form positive ions. 20. You accidentally drop a piece of metal into B. They lose electrons to form Metals tend to have low ionization energies, meaning they vinegar, and it starts reacting. Which of the positive ions. B. They lose electrons to form readily lose electrons to achieve a stable electron following describes how metal atoms typically C. They gain electrons to form positive ions. configuration. This loss of electrons results in the formation form ions? positive ions. of positively charged ions (cations). D. They share electrons to form positive ions. A. They are less likely to form bonds. B. They lose electrons to Non-metals have a high electron affinity, meaning they have a achieve stability. D. They attract more electrons strong tendency to gain electrons to achieve a stable electron 21. Why do non-metals tend to form anions? C. They have more protons than due to high electron affinity. configuration. This gain of electrons results in the formation electrons. of negatively charged ions (anions). D. They attract more electrons due to high electron affinity. A. Fluorine 22. Which element is most likely to form a B. Oxygen Sodium (Na) is an alkali metal and readily loses its outermost positive ion (cation) during chemical C. Sodium C. Sodium electron to form a stable cation (Na⁺). reactions? D. Sulfur A. It loses one electron to become Al⁺ 23. When you place a piece of aluminum in a B. It gains one electron to beaker of hydrochloric acid (HCl), hydrogen become Al⁻ C. It loses three electrons to Aluminum (Al) has three valence electrons and loses them to gas bubbles form. Aluminum loses electrons C. It loses three electrons to become Al³⁺ form a stable cation (Al³⁺). and forms ions in this reaction. What happens become Al³⁺ to aluminum during this process? D. It gains three electrons to become Al³⁻ Question Choices Answer Explanation 24. When considering the structure of a Carbon has four valence electrons, which are involved in diamond, how many electrons does each A. 2 B. 4 C. 6 D. 8 B. 4 forming covalent bonds with other carbon atoms in the carbon atom have in its outermost shell? diamond structure. 25. In organic chemistry, how many bonds can Carbon has four valence electrons and can form four a single carbon atom form with its neighboring A. 2 B. 4 C. 6 D. 8 B. 4 covalent bonds with other atoms, including carbon, atoms? hydrogen, oxygen, and nitrogen. A. One shared pair of electrons A carbon-carbon triple bond involves the sharing of three 26. When designing materials for strong B. Two shared pairs of electrons C. Three shared pairs of pairs of electrons between the two carbon atoms. This adhesives, which description fits a carbon- C. Three shared pairs of electrons results in a very strong and rigid bond, making it an ideal carbon triple bond? electrons component for strong adhesives. D. No shared pair of electrons A. Ionic bond Carbon most commonly forms covalent bonds with other 27. What type of bonds does carbon most B. Metallic bond atoms. This is because carbon has four valence electrons, C. Covalent bond commonly form with other atoms? C. Covalent bond allowing it to share electrons with other atoms to achieve a D. Both A and C stable octet configuration. A. Its high atomic mass. B. Its ability to form ionic bonds Carbon's ability to form four covalent bonds is the primary 28. When considering why carbon is a key C. Its ability to form hydrogen D. Its ability to form four reason for its central role in organic molecules. This allows element in organic molecules, what makes it bonds. covalent bonds. carbon to bond with itself and other atoms, creating complex unique compared to other elements? D. Its ability to form four and diverse structures. covalent bonds. A. Its small atomic size Carbon's four valence electrons are the key to its versatility. B. Its large atomic number 29. In the chemistry of life, what allows carbon These electrons allow carbon to form four covalent bonds C. Its four valence electrons C. Its four valence electrons to create such a wide variety of compounds? with other atoms, creating a vast array of possible structures D. Its ability to gain electrons and functional groups. easily Question Choices Answer Explanation A. It loses electrons easily. B. It is highly electronegative. Carbon's ability to form single, double, and triple 30. Which of the following best explains why C. It has strong metallic D. It can form single, double, bonds contributes significantly to its stability and versatility. carbon can form stable bonds with itself and properties. and triple bonds. This allows for a wide range of bond lengths and strengths, other elements? D. It can form single, double, leading to diverse molecular shapes and properties. and triple bonds. In diamond, each carbon atom forms four strong covalent bonds with four other carbon atoms. These bonds are A. Linear 31. What type of structure does carbon form arranged in a tetrahedral geometry, where the carbon atom is B. Hexagonal when it bonds with other carbon atoms in a C. Tetrahedral at the center and the four other carbon atoms are located at C. Tetrahedral three-dimensional network, like in a diamond? the corners of a tetrahedron. This results in a rigid, three- D. Trigonal planar dimensional network structure that gives diamond its exceptional hardness and high melting point. A. Carbon atoms in graphene Graphene's exceptional electrical conductivity arises from absorb protons. the unique bonding arrangement of its carbon atoms. 32. In graphene, a single layer of carbon atoms, B. Carbon atoms in graphene Each carbon atom forms three strong covalent bonds with its electrons move freely across the surface. form triple bonds. D. Carbon atoms in graphene neighbors, forming a hexagonal lattice. This leaves one free- What property of carbon allows graphene to C. Carbon atoms in graphene have free-moving electrons. moving electron per carbon atom, which can easily move conduct electricity? form strong ionic bonds. throughout the graphene sheet, allowing for efficient D. Carbon atoms in graphene electrical conduction. have free-moving electrons. The sharing of more electron pairs between two carbon A. Bond strength increases atoms leads to a stronger bond. This is because the 33. As two carbon atoms share more electron B. Bond strength decreases increased electron density between the atoms creates a pairs, what effect does this have on their bond C. Bond strength fluctuates A. Bond strength increases greater electrostatic attraction, making the bond more strength? D. Bond strength remains the difficult to break. For example, a double bond is stronger than same a single bond, and a triple bond is stronger than a double bond. Question Choices Answer Explanation A. It is abundant in nature. Carbon's ability to form stable bonds with various B. It can only form single bonds. elements is the primary reason for its fundamental role in 34. Which of the following best explains why C. It forms strong ionic bonds D. It forms stable bonds with life. This allows for the construction of complex and carbon is essential for life? with metals. various elements. diverse organic molecules, such as carbohydrates, proteins, D. It forms stable bonds with lipids, and nucleic acids, which are essential for all living various elements. organisms. As the carbon chain length in hydrocarbons increases, A. Boiling point increases the boiling point increases. This is due to the increased van 35. What is the effect of increased carbon B. Boiling point decreases der Waals forces between the longer chains. These forces are chain length on the boiling point of C. Boiling point fluctuates A. Boiling point increases weak intermolecular attractions that increase with the hydrocarbons? D. Boiling point remains the surface area of the molecules. Longer chains have a larger same surface area, leading to stronger van der Waals forces and a higher boiling point. The molecular weight and chain length of a hydrocarbon are A. The boiling point the primary factors determining its physical state at room 36. What is the primary factor determining the B. The presence of oxygen temperature. Hydrocarbons with shorter chains and lower D. The molecular weight and physical state (solid, liquid, gas) of a C. The color of the compound molecular weights tend to be gases at room temperature, chain hydrocarbon at room temperature? D. The molecular weight and while those with longer chains and higher molecular weights chain are liquids or solids. This is directly related to the strength of van der Waals forces, as discussed in the previous question. As the molecular weight of hydrocarbons increases, their density also tends to increase. This is because the molecules become heavier and pack more tightly together. A. Density The other options are incorrect: 37. Which physical property tends to increase B. Solubility in water - Solubility in water: Hydrocarbons are generally nonpolar as the molecular weight of hydrocarbons A. Density C. Electrical conductivity and therefore do not dissolve well in water, which is a polar rises? D. Reactivity with oxygen solvent. - Electrical conductivity: Hydrocarbons are generally poor conductors of electricity due to the lack of free-moving electrons. Question Choices Answer Explanation - Reactivity with oxygen: While hydrocarbons can react with oxygen in combustion reactions, their reactivity does not increase significantly with molecular weight. A. Their ability to dissolve in water Aromatic hydrocarbons are characterized by a ring structure 38. When comparing different types of B. The presence of only single with alternating double bonds. This structure, known as hydrocarbons, what characteristic bonds D. The ring structure with an aromatic ring, is particularly stable due to the distinguishes aromatic hydrocarbons from C. Their solid state at room alternating double bonds delocalization of electrons. Aliphatic hydrocarbons, on the aliphatic hydrocarbons? temperature other hand, lack this ring structure and consist of straight or D. The ring structure with branched chains of carbon atoms. alternating double bonds A. They are only produced artificially. B. They contain a carbonyl Hydrocarbons are organic compounds that are composed 39. Which of the following is a characteristic of functional group. D. They are composed only of only of carbon and hydrogen. They are found naturally in hydrocarbons? C. They contain carbon, carbon and hydrogen. fossil fuels like oil and gas and are also synthesized in various hydrogen, and nitrogen. industrial processes. D. They are composed only of carbon and hydrogen. A. Gasoline and acetone 40. When preparing for a camping trip, which of B. Water and ethyl alcohol Both liquefied petroleum gas (LPG) and kerosene are highly the following pairs of organic compounds C. Lubricating oil and isopropyl D. Liquefied petroleum gas flammable hydrocarbons and should be handled with would you need to handle with extra caution alcohol and kerosene extreme caution, especially outdoors. due to their high flammability? D. Liquefied petroleum gas and kerosene 41. Nimfa scratched herself when her arm A. Water Isopropyl alcohol is a common antiseptic that helps to kill D. Isopropyl Alcohol bumped against the concrete post. What do B. Formalin germs and prevent infection on minor wounds. Question Choices Answer Explanation you think she should apply to keep her bruise C. Acetone free from harmful germs? D. Isopropyl Alcohol 42. While shopping at the grocery store, you A. Sucrose in candy Ethanol (C₂H₅OH) is the type of alcohol found in alcoholic come across several beverages. Which of the B. Glucose in a soft drink D. Ethanol in a bottle of wine beverages. Sucrose and glucose are sugars, while acetic acid following compounds is classified as an C. Acetic acid in vinegar is a carboxylic acid found in vinegar. alcohol? D. Ethanol in a bottle of wine 43. In a funeral home, embalmers prepare A. Acetone Formaldehyde (CH₂O) is a common embalming fluid used to human cadavers for viewing. Which organic B. Ethanol C. Formaldehyde preserve the bodies. It acts as a disinfectant and helps to compound do they commonly use in this C. Formaldehyde slow down decomposition. process to preserve the bodies? D. Glycerol A. Amine group (–NH₂) The hydroxyl group (-OH) is the defining functional group of 44. Which functional group is present in B. Carbonyl group (C=O) alcohols. The presence of this polar group gives alcohols alcohols, making them effective solvents in C. Hydroxyl group (–OH) C. Hydroxyl group (–OH) their solvent properties, making them effective in many many household products? D. Carboxyl group (–COOH) household products. 45. Which organic compound is known for A. Acetone Ethylene (C₂H₄) is a plant hormone that accelerates the hastening the ripening of fruits and is B. Ethyne C. Ethylene ripening of fruits. It is produced when calcium carbide reacts produced when calcium carbide reacts with C. Ethylene with water. water? D. Ethanol A. Alkenes exist primarily as gases, while alkanes are often 46. When studying the various classes of D. Alkenes contain at least found as solids at room hydrocarbons, it's important to understand the one double bond between Alkenes are unsaturated hydrocarbons containing at least temperature. key differences in their structures and carbon atoms, whereas one carbon-carbon double bond. Alkanes are saturated B. Alkenes are composed bonding. Which of the following statements alkanes are defined by their hydrocarbons containing only single bonds between carbon exclusively of carbon atoms, correctly identifies the distinguishing feature single bonds connecting atoms. whereas alkanes contain that differentiates alkenes from alkanes? carbon atoms. oxygen atoms in their structure. C. Alkenes are characterized by Question Choices Answer Explanation the presence of triple bonds between carbon atoms, while alkanes exclusively contain single bonds. D. Alkenes contain at least one double bond between carbon atoms, whereas alkanes are defined by their single bonds connecting carbon atoms. A. Atom Ionic compounds are composed of ions held together by 47. What is the representative particle of ionic B. Ion D. Formula unit electrostatic forces. The smallest repeating unit in an ionic compounds? C. Molecule compound is called a formula unit. D. Formula unit A. 3.01 x 10^23 48. How many particles are there in one mole B. 3.01 x 10^24 One mole of any substance contains 6.02 x 10^23 particles, C. 6.02 x 10^23 of any kind of substance? C. 6.02 x 10^23 which is known as Avogadro's number. D. 6.02 x 10^24 A. Ann: Different sets of materials having the same mass have different number of pieces. B. Dan: Different sets of 49. Who among the following students Ann is correct because different sets of materials with the materials have the same describes the result of the activity on counting A. Ann same mass can have different numbers of pieces if the number of pieces and the same by weighing correctly? materials have different densities. mass. C. Tom: The same sets of materials, have the same number of pieces but different masses. Question Choices Answer Explanation D. Ann B. Dan C. Tom D. None of them A. It can be applied to any type of particle representative. 50. In a chemistry lab, a student needs to The mole concept is essential for quantitative chemistry B. It gives us a convenient way prepare a solution and convert grams of a because it provides a standard unit for counting large to express large numbers. compound to the number of molecules for the D. All of the above numbers of atoms, molecules, or ions. It allows us to relate C. It is useful when converting right concentration. Why is the mole concept mass to the number of particles and to perform calculations between grams and atoms or essential in this task? involving chemical reactions. molecules. D. All of the above 51. People usually use hydrogen peroxide A. 0.025 mole (H₂O₂, Molar Mass = 34.02 g/mole) to clean B. 0.029 mole To calculate the number of moles, divide the mass by the their wounds. If Cheska used 1.0 g of H₂O₂ to B. 0.029 mole C. 0.030 mole molar mass: 1.0 g / 34.02 g/mol = 0.029 mole. clean her wound, how many moles of H₂O₂ did D. 0.035 mole she use? 52. Ethyl butanoate (C3H7COOC2H5) is the A. 110 g/mole Add up the atomic masses of each element in the formula: (3 substance responsible for the aroma of B. 116 g/mole B. 116 g/mole x 12.01) + (7 x 1.01) + 12.01 + 16.00 + 12.01 + (5 x 1.01) = pineapple. What is the molar mass of ethyl C. 126 g/mole 116.16 g/mol. butanoate? D. 130 g/mole 53. Calcium carbonate (CaCO₃, Molar Mass = 1. Convert mg to g: 250 mg = 0.25 g. 2. Calculate moles per 100.09 g/mole) is an antacid used to neutralize A. 0.0225 mole tablet: 0.25 g / 100.09 g/mol = 0.0025 mol. 3. Calculate total excess acid in the stomach. Lorie has been B. 0.0235 mole A. 0.0225 mole moles per day: 0.0025 mol/tablet x 3 tablets/day = 0.0075 prescribed a 250 mg tablet of CaCO₃ to take C. 0.0242 mole mol/day. 4. Calculate total moles over 3 days: 0.0075 three times a day. How many moles of CaCO₃ D. 0.0252 mole mol/day x 3 days = 0.0225 mol. will Lorie consume over 3 days? Question Choices Answer Explanation 54. What is the percentage composition of A. 11% B. 11% 1. Calculate the molar mass of water: (2 x 1.01) + 16.00 = hydrogen in water (H₂O)? B. 33% 18.02 g/mol. 2. Calculate the mass of hydrogen in one mole C. 50% of water: 2 x 1.01 = 2.02 g. 3. Divide the mass of hydrogen by D. 67% the molar mass of water and multiply by 100%: (2.02 g / 18.02 g/mol) x 100% = 11.21% ≈ 11%. A. 12 g/mole 55. What is the molar mass of carbon dioxide B. 28 g/mole Add the atomic masses of carbon and oxygen: 12.01 g/mol + D. 44 g/mole (CO₂)? C. 32 g/mole (2 x 16.00 g/mol) = 44.01 g/mol. D. 44 g/mole 56. Which of the following compounds has a A. Glucose B. Ethanol C. They Calculate the percentage of oxygen in each compound: higher percentage of oxygen: glucose (C₆H₁₂O₆) are equal. D. Cannot be A. Glucose - Glucose: (6 x 16.00 g/mol) / 180.16 g/mol x 100% = 53.3% or ethanol (C₂H₅OH)? determined - Ethanol: (1 x 16.00 g/mol) / 46.07 g/mol x 100% = 34.7% 1. Determine the empirical formula: - Assume a 100g sample and calculate moles of each element: - Carbon: (60g / 12.01 g/mol) = 4.99 mol - Hydrogen: (13.33g / 1.01 g/mol) = 13.2 mol - Oxygen: (26.67g / 16.00 g/mol) = 1.67 mol - Divide each mole value by the smallest mole value (1.67 57. A compound contains 60% carbon, 13.33% A. C9H24O3 mol) to find the simplest whole-number ratio: hydrogen, and 26.67% oxygen. If the molar B. C₁₃H₁₆O₃ B. C₁₃H₁₆O₃ - Carbon: 4.99 mol / 1.67 mol ≈ 3 mass is 180 g/mol, what is the molecular C. C₅H₁₀O₅ - Hydrogen: 13.2 mol / 1.67 mol ≈ 8 formula? D. C₂H₁₅O₂ - Oxygen: 1.67 mol / 1.67 mol = 1 - The empirical formula is C₃H₈O. 2. Calculate the empirical formula mass: - (3 x 12.01 g/mol) + (8 x 1.01 g/mol) + (1 x 16.00 g/mol) = 60.07 g/mol 3. Determine the molecular formula: - Divide the given molar mass (180 g/mol) by the empirical formula mass (60.07 g/mol): 180 g/mol / 60.07 g/mol ≈ 3 Question Choices Answer Explanation - Multiply the subscripts in the empirical formula by 3: - C₃H₈O x 3 = C₉H₂₄O₃ 1. Assume a 100g sample and calculate moles: - Carbon: (30g / 12.01 g/mol) = 2.5 mol - Hydrogen: (10g / 1.01 g/mol) = 9.9 mol A. C2H8O3 - Oxygen: (60g / 16.00 g/mol) = 3.75 mol 2. Divide by the 58. A compound contains 10% hydrogen, 30% B. CH3O smallest mole value (2.5 mol) to find the simplest ratio: carbon, and 60% oxygen. What is the empirical B. CH₃O C. C3H8O - Carbon: 2.5 mol / 2.5 mol = 1 formula? D. C2H6O2 - Hydrogen: 9.9 mol / 2.5 mol ≈ 4 - Oxygen: 3.75 mol / 2.5 mol = 1.5 3. Since the ratio of oxygen is 1.5, multiply all subscripts by 2 to get whole numbers: - The empirical formula is CH₃O A. 10.53% 1. Calculate the molar mass of oxygen in the compound: 59. If a compound with the formula C₅H₁₁O₂ B. 18.42% - (2 x 16.00 g/mol) = 32.00 g/mol 2. Divide the molar mass of has a molar mass of 114 g/mol, what is the C. 28.95% C. 28.95% oxygen by the total molar mass and multiply by 100%: percentage of oxygen in the compound? D. 31.07% - (32.00 g/mol / 114 g/mol) x 100% = 28.95% A. Subtract the atomic mass of hydrogen from nitrogen. B. Multiply the atomic mass of The percentage of an element in a compound is calculated by nitrogen by the number of dividing the element's atomic mass by the compound's total hydrogens. D. Divide the atomic mass of 60. Rita is tasked with determining the molar mass and then multiplying by 100%. In this case, the C. Add the atomic masses of all nitrogen by the total molar percentage of nitrogen in ammonia (NH3). How atomic mass of nitrogen is 14.01 g/mol, and the molar mass the atoms in the formula and mass of NH3 and multiply by should she calculate it? of NH3 is 17.03 g/mol. Therefore, the percentage of nitrogen divide by the molar mass. 100. in ammonia is: (14.01 g/mol / 17.03 g/mol) x 100% = 82.35%. D. Divide the atomic mass of Option D correctly describes this calculation. nitrogen by the total molar mass of NH3 and multiply by 100.