Chemical Quantities and Chemical Reactions Exam Prep Ch4

Test questions for Chapter 4

Chemical Quantities and Chemical Reactions

1. What is a biochemical pathway?
   1. the path that nutrients take through the body when they are metabolized
   2. the complex blood transport system
   3. a chemical reaction in the body that releases energy
   4. a chemical reaction that releases carbon dioxide
   5. a particular sequence of chemical reactions in the body
2. Where in the body does ethanol metabolism occur?
   1. the stomach
   2. the liver
   3. the kidneys
   4. the small intestine
   5. the mouth
3. Calculate the molecular mass of aspirin, C₉H₈O₄.
   1. 29 g/mole
   2. 126 g/mole
   3. 180. g/mole
   4. 126 amu
   5. 180. amu
4. What is the mass of one mole of the hydroxide ion (^-OH)?
   1. 8 g
   2. 15 g
   3. 17 g
   4. 7 g
   5. 5 g
5. The ionic compound CaCO₃ has a formula mass of
   1. 50 g/mole.
   2. 50 amu.
   3. 100 g/mole.
   4. 100 amu.
   5. 68.1 amu.
6. Which of the following statements describes how formula mass and molecular mass differ?
   1. A formula mass is measured in amu, whereas a molecular mass is measured in grams/mole.
   2. A formula mass is measured in grams/mole, whereas a molecular mass is measured in amu.
   3. A formula mass is the mass of one unit of an ionic lattice, whereas molecular mass is the mass of one molecule.
   4. A formula mass is the mass of one molecule, whereas molecular mass is the mass of one unit of an ionic lattice.
   5. There is no difference between these terms.
7. Which of the following statements describes how molecular mass and molar mass differ?
   1. Molecular mass is measured in amu, whereas molar mass is measured in grams/mole.
   2. Molar mass is measured in amu, whereas molecular mass is measured in grams/mole.
   3. A molar mass is the mass of one unit of an ionic lattice, whereas molecular mass is the mass of one molecule.
   4. A molar mass is the mass of one molecule, whereas molecular mass is the mass of one unit of an ionic lattice.
   5. There is no difference between these terms.
8. Which statement best describes why we use moles when measuring quantities of atoms and molecules?
9. Moles are used because they are units of mass.
10. Moles are used because one mole is the same numerical value as the atomic mass of an element.
11. Moles are used because atoms and molecules are too small to measure singly.
12. Moles are used because chemists like moles.
13. Moles are not involved in measuring quantities of atoms and molecules.
14. Which of the following values is Avogadro’s number?
    1. 6
    2. 6.02
    3. 6.02 × 10²³
    4. 6.02 × 10²⁶
    5. 6.02 × 10¹²³
15. How many carbon atoms are in 1 mole of carbon?
    1. 1
    2. 12
    3. 12.011
    4. 6
    5. 6.02 × 10²³
16. How many moles of carbon are in 27.1 g of carbon?
17. 2.26 moles
18. 325 moles
19. 0.443 moles
20. 4.52 moles
21. 163 moles
22. How many moles is 9.1 × 10²⁴ ions of Na⁺?
    1. 5.5 × 10⁴⁸ moles
    2. 0.17 moles
    3. 1 mole
    4. 15 moles
    5. 0.67 moles
23. How many copper atoms are in 0.5 moles of copper?
    1. 0.5
    2. 14
    3. 3
    4. 6.02 × 10¹²
    5. 3.01 × 10²³
24. How many grams of iron are in 1.28 moles of iron?
25. 0.0230 g
26. 20.3 g
27. 33.3 g
28. 43.6 g
29. 71.4 g
30. A molecule of oxygen, O₂, has a molar mass of 32.00 g/mole. What is the mass of 4.52 × 10²³ O₂ molecules?
    1. 24 grams
    2. 4.52 × 10²³ amu
    3. 4.52 × 10²³ grams
    4. 0.75 grams
    5. 0.23 grams
31. Calculate the mass of one mole of dopamine, a neurotransmitter with the molecular formula C₈H₁₁NO₂.
32. 22.0 g
33. 43.0 g
34. 82.0 g
35. 153 g
36. 164 g
37. Which of the following equations best describes how to calculate the molar mass of Mg(OH)₂?
38. 24.3 g/mole + 16.0 g/mole + 1.01 g/mole
39. 24.3 g/mole + 16.0 g/mole + (2 × 1.01 g/mole)
40. 24.3 g/mole + (2 × 16.0 g/mole) + 1.01 g/mole
41. 24.3 g/mole + 2 × (16.0 g/mole + 1.01 g/mole)
42. 2 × (24.3 g/mole + 16.0 g/mole + 1.01 g/mole)
43. Does one mole of the antibiotic penicillin G (C₁₆H₁₈N₂O₄S) weigh more or less than one mole of the antibiotic streptomycin (C₂₁H₃₉N₇O₁₂)?
44. Actually, they should weigh the same because a mole always has the same mass.
45. Actually, they should weigh the same because a mole always has the same number of particles in it.
46. Streptomycin should weigh more because its individual molecules are larger.
47. Penicillin should weigh more because its individual molecules are larger.
48. It is not possible to determine which one would weigh more because mole size varies.
49. How many moles of the antibiotic tetracycline (C₂₂H₂₄N₂O₈) are in a 50-mg dose?
50. 8880 moles
51. 22.2 moles
52. 8.88 moles
53. 0.113 moles
54. 1.13 × 10⁻⁴ moles
55. An infant dose of acetaminophen (C₈H₉NO₂) is 0.080 g. How many molecules of acetaminophen are in each infant dose?
    1. 5.3 × 10^-4 molecules
    2. 3.2 × 10²⁰ molecules
    3. 7.2 × 10²³ molecules
    4. 1.2 molecules
    5. 2 × 10^-24 molecules
56. A normal blood oxygen (O₂) level is 8.0 mmol/L. What is the normal mass of oxygen per liter of blood?
57. 2.50 × 10⁻⁴ g
58. 0.256 g
59. 4.00 g
60. 256 g
61. 2.56 × 10⁵ g
62. Which of the following equations is used to convert 91.0 milligrams of urea (CH₄N₂O) to moles of urea?

a. 91.0 mg × 1000 g × 1 mole

1 mg 60.0 g

b. 91.0 mg × 1000 g × 60.0 g

1 mg 1 mole

c. 91.0 mg × 1 g___ × 60.0 mole

1000 mg 1 g

d. 91.0 mg × 1 g_____ × 1 mole

1000 mg 60.0 g

e. 91.0 mg × 1 g___ × 60.0 g

1000 mg 1 mole

1. Jane Doe has her cholesterol measured and the resulting lab report gives a value of 0.548 × 10^-3 mol/dL. You know that the normal range of cholesterol (C₂₇H₄₆O) is 0.100 – 0.240 g/dL. Is Jane Doe’s cholesterol within the normal range?
   1. No, it is above 0.240 g/dL.
   2. No, it is below 0.100 g/dL.
   3. Yes, it is between 0.100 g/dL and 0.240 g/dL.
   4. Yes, it is above 0.240 g/dL.
   5. Yes, it is below 0.100 g/dL.
2. If Jane Doe has a blood carbon dioxide concentration of 0.022 mol/L, how many carbon dioxide molecules are in each liter of her blood?
3. 3.7 × 10⁻²⁶
4. 0.022
5. 1.32 × 10²²
6. 6.02 × 10²³
7. 2.7 × 10²⁵
8. If Jane Doe has a blood glucose (C₆H₁₂O₆) concentration of 0.102 g/dL, how many glucose molecules does she have in each deciliter of blood?
9. 3.41 × 10²⁶
10. 3.41 × 10²³
11. 3.41 × 10²⁰
12. 6.41 × 10²²
13. 5.67 × 10⁻⁴
14. Jane Doe has a cholesterol (C₂₇H₄₆O) count of 178 mg/dL. You would like to calculate the number of cholesterol molecules that Jane Doe has in each deciliter of blood. Which of the following unit conversions are required to calculate the number of cholesterol molecules per deciliter?

I. 10 dL II. 1 mole III. 1 g____ IV. 6.02 × 10²³ molecules

1 L 387 g 1000 mg 1 mole

a. All of the conversions are needed.

b. I and IV

c. III and IV

d. I, II, and III

e. II, III, and IV

1. Jane Doe has a cholesterol (C₂₇H₄₆O) count of 178 mg/dL. You would like to calculate the number of cholesterol molecules that Jane Doe has in each deciliter of blood. Which of the following calculations is used to solve this problem?

a. 178 mg × 1000 g × 1 mole × 6.02 × 10²³ molecules

dL 1 mg 387 g 1 mole

b. 178 mg × 1 g___ × 387 mole × 6.02 × 10²³ molecules

dL 1000 mg 1 g 1 mole

c. 178 mg × 1 g___ × 387 mole × 1 molecule_____

dL 1000 mg 1 g 6.02 × 10²³ mole

d. 178 mg × 1000 g___ × 1 mole × 1 molecule_____

dL 1 mg 387 g 6.02 × 10²³ mole

e. 178 mg × 1 g___ × 1 mole × 6.02 × 10²³ molecules

dL 1000 mg 387 g 1 mole

1. Jane Doe has a cholesterol (C₂₇H₄₆O) count of 178 mg/dL. How many cholesterol molecules does Jane Doe have in each deciliter of blood?
2. 7.64 × 10^-22
3. 1.14 × 10^-22
4. 2.77 × 10²⁰
5. 4.45 × 10²⁵
6. 2.77 × 10²⁶
7. Which of the following transformations is a chemical reaction?
8. water boiling
9. burning wood
10. condensation on the outside of a water glass
11. dry ice changing from a solid to a gas
12. All of the above
13. Which of the following must occur for there to be a chemical reaction?
14. Heat is released.
15. There is a change of state.
16. A gas is produced.
17. Bonds break and/or new ones are formed.
18. All of the above
19. A chemical reaction involves many changes, but not everything changes during a reaction. Which of the following is NOT a change that occurs during a chemical reaction?
20. Atoms change in number or identity.
21. Bonds break.
22. Heat is released and/or absorbed.
23. New bonds form.
24. New molecules are formed.
25. How is a nuclear reaction different from a chemical reaction?
    1. They are identical.
    2. Only in a chemical reaction can atoms change into different atoms.
    3. Chemical reactions involve only the nucleus of the atom.
    4. Only in a nuclear reaction can atoms change into different atoms.
    5. Nuclear reactions release energy and chemical reactions absorb energy.

1. Below are several statements. Which of these statements apply to chemical reactions?
   • • 1. A chemical reaction always involves two reactants.
       2. Physical changes are a type of chemical reaction.
       3. Energy changes are involved in chemical reactions.
       4. Atoms are gained and lost during a chemical reaction.
       5. Bonds are broken and new bonds formed during a chemical reaction.
2. All of these statements apply to chemical reactions.
3. Only I applies to chemical reactions.
4. I, II, and III all apply to chemical reactions.
5. IV and V both apply to chemical reactions.
6. III and V both apply to chemical reactions.
7. Which of these figures illustrate chemical reactions?

1. I, II, and III are all chemical reactions.
2. Only I and II are chemical reactions.
3. Only I and III are chemical reactions.
4. Only II and III are chemical reactions.
5. None of these figures are chemical reactions.
6. Which of the following transformations is illustrated in Figure II?

1. Figure II illustrates the breaking of hydrogen bonds.
2. Figure II illustrates the breaking of covalent bonds.
3. Figure II illustrates a chemical reaction.
4. Figure II illustrates a nuclear reaction.
5. Figure II illustrates a chemical reaction.
6. Which of the figures violates the conservation of mass?

1. All of these figures violate the conservation of mass.
2. Figure I violates the conservation of mass.
3. Figure II violates the conservation of mass.
4. Figure III violates the conservation of mass.
5. Figures II and III both violate the conservation of mass.
6. In which figure are new O-H bonds being formed?

1. Figure I
2. Figure II
3. Figure III
4. Figures I and II
5. Figures I and III
6. What are the products of the reaction illustrated in Figure I?

1. CH₄ and O₂
2. CO₂ and H₂O
3. CH₄ only
4. O₂ only
5. CO₂ only
6. Hydrogen fuel cells are a promising alternative to gasoline engines in part because they release water instead of carbon dioxide. In a hydrogen fuel cell, hydrogen gas (H₂) and oxygen gas (O₂) react to make water as shown below. Which of the following statements is a true statement about how this reaction occurs?

2 H₂(g) + O₂(g) → 2 H₂O(g)

1. Two molecules of H₂ and a molecule of O₂ must collide at one time.
2. A molecule of H₂ and a molecule of O₂ collide.
3. An O-H bond must break.
4. An H-H bond must form.
5. The reactants must undergo a change of state for this reaction to occur.
6. An important part of metabolism is the breakdown of proteins into smaller parts called amino acids. During the course of this reaction, some bonds are broken and others are formed. Select the choice that correctly lists the bonds that are broken and those that are formed.

1. The following reaction is the formation of a peptide from two amino acids. This sort of reaction occurs in the body as part of the synthesis of proteins. This reaction is missing a component. Which of the following is missing?

2 NH₂CH₂COOH → NH₂CH₂CONHCH₂COOH

1. Nothing is missing.
2. H₂O is missing from the reactant side of the equation.
3. H₂O is missing from the product side of the equation.
4. O₂ is missing from the reactant side of the equation.
5. O₂ is missing from the product side of the equation.
6. Your friend combines vinegar (which contains acetic acid, CH₃COOH) and baking soda (NaHCO₃) and ends up with a runny foam. Your friend is pretty sure that the reaction produces water and carbon dioxide, which he can see just by looking at the foam, but he is unsure of what else the reaction produces. Given the partial reaction below, what do you tell your friend?

NaHCO₃ + CH₃COOH → H₂O + CO₂ + ?

1. This reaction also produces CH₃COONa.
2. This reaction also produces CH₄.
3. This reaction also produces O₂.
4. This reaction only produces H₂O and CO₂.
5. This reaction probably produces something else, but it is not possible to determine the identity of the other product(s).
6. What does it mean for mass to be conserved?
7. Mass is neither created nor destroyed in the course of a chemical reaction.
8. Mass is a valuable resource and should not be wasted.
9. Molecules do not degrade under normal circumstances.
10. Atoms sometimes disappear over the course of a chemical reaction.
11. Atoms sometimes appear, disappear or are changed over the course of a chemical reaction.
12. Under what circumstances is mass conserved?
13. Mass is conserved only in the laboratory.
14. Mass is conserved only theoretically.
15. Mass is conserved everywhere except the human body.
16. Mass is conserved in nature, but not in the laboratory.
17. Mass is conserved during all chemical reactions.
18. Hydrogen peroxide loses its potency when it is stored for extended periods of time because it spontaneously breaks down. The following figure illustrates this breakdown, but it is missing a product molecule. Which of the following symbols represents the missing product in this reaction?

= H

= O

a.

b.

c.

d.

e.

1. What is the primary relationship between a chemical reaction and a chemical equation?
2. There is no relationship between a chemical reaction and a chemical equation.
3. A chemical equation is the written representation of a chemical reaction.
4. A chemical equation follows the law of conservation of mass but a chemical reaction does not.
5. A chemical equation shows the proportion of reactants and products but a chemical reaction does not necessarily reflect those proportions.
6. Chemical equations and chemical reactions are exactly the same thing.
7. Which of the following characteristics of a chemical reaction is never included in a chemical equation?
8. the quantity of reactants
9. the relative proportions of reactants and products
10. the amount of energy absorbed or released by the reaction
11. the identity of the products and reactants
12. the physical state of the reactants and products
13. The balanced equation for the combustion of propane is given below. What do the numbers in front of the molecules (the coefficients) mean?

CH₃CH₂CH₃ + O₂ → 3 CO₂ + 4 H₂O

1. Three molecules of CO₂ are produced when one molecule of CH₃CH₂CH₃ reacts with one molecule of O₂.
2. Six molecules of CO₂ are produced when two molecules of CH₃CH₂CH₃ react with two molecules of O₂.
3. Nine moles of CO₂ are produced when three moles of CH₃CH₂CH₃ react with three moles of O₂.
4. Four moles of H₂O are produced when one mole of CH₃CH₂CH₃ reacts with one mole of O₂.
5. All of the above
6. The balanced equation for nitrogen fixing is given below. What do the numbers in front of the molecules (the coefficients) mean?

N₂ + 3 H₂ → 2 NH₃

1. Three moles of H₂ react with one mole of N₂ to give two moles of NH₃.
2. Three grams of H₂ react with one gram of N₂ to give two grams of NH₃.
3. Three atoms of H react with one atom of N to give two molecules of NH₃.
4. Two grams of N react with six grams of H to give eight grams of NH₃.
5. All of the above
6. Coefficients are important components of chemical equations. What is the significance of coefficients in a chemical equation?
7. Coefficients indicate the ratio of masses of molecules.
8. Coefficients indicate the ratio of numbers of atoms and molecules.
9. Coefficients indicate the ratio of numbers of moles of molecules and atoms.
10. I only
11. II only
12. III only
13. I and II
14. II and III

1. The industrial nitrogen fixing reaction used in the preparation of fertilizers and other nitrogen containing compounds is called the Haber process. The chemical equation for this process is shown below. According to this reaction, how many moles of ammonia would you produce if you reacted one mole of N₂ with three moles of H₂?

N₂ + 3 H₂ → 2 NH₃

1. 0
2. 1
3. 2
4. 3
5. 4
6. During metabolism, table sugar (sucrose) is broken down into monosaccharides. According to the following chemical equation, how many moles of monosaccharides will be produced when 6 moles of sucrose react with 6 moles of water?

C₁₂H₂₂O₁₁ + H₂O → 2 C₆H₁₂O₆

sucrose monosaccharides

1. 0
2. 2
3. 4
4. 6
5. 12
6. During metabolism, table sugar (sucrose) is broken down into monosaccharides. Which of the following equations could you use to determine the moles of monosaccharides produced when 3 moles of sucrose react with 3 moles of water?

C₁₂H₂₂O₁₁ + H₂O → 2 C₆H₁₂O₆

sucrose monsaccharides

1. In the body, glucose is broken down in the presence of oxygen into carbon dioxide and water. The balanced chemical equation for this reaction is shown below. According to this equation, how many molecules of carbon dioxide are produced when three molecules of glucose are metabolized in the presence of 18 moles of oxygen?

C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O

1. 0
2. 6
3. 12
4. 18
5. 24
6. Below are several chemical equations, each labeled with the names of parts of a chemical equation. Which has the parts labeled correctly.

1. What is the meaning of the arrow in the following chemical equation?

1. Heat is released from the reaction.
2. A product is substituted for a reactant.
3. The reactants collide.
4. The reactants are transformed into the products.
5. Heat is applied to the reactants.
6. Which of the following reactions is balanced?
7. CH₃CH₂CH₃ + O₂ → CO₂ + H₂O
8. CH₃CH₂CH₃ + O₂ → 3 CO₂ + 4 H₂O
9. CH₃CH₂CH₃ + 10 O₂ → 3 CO₂ + 4 H₂O
10. CH₃CH₂CH₃ + 5 O₂ → 3 CO₂ + 4 H₂O
11. None of these are balanced.
12. What does it mean for a chemical equation to be balanced?
13. A balanced chemical equation describes a chemical reaction found in nature.
14. A balanced chemical equation describes a chemical reaction that produces only some product, so there is an equal amount of reactant and product.
15. A balanced chemical equation contains an equal number of each type of atom on both sides of the equation.
16. A balanced chemical equation can run either forward or backward.
17. A balanced chemical equation represents a chemical reaction that is part of metabolism.
18. The following chemical equation is not balanced. What must be done to the equation to make it balanced?

Al(s) + CuO(s) → Al₂O₃(s) + Cu(s)

1. Change the coefficients to: 2 for Al, 3 for CuO and 3 for Cu.
2. Change the subscripts of CuO to CuO₃.
3. Add a molecule of AlO.
4. Change the state of matter in the reactants.
5. Change the subscripts of Al₂O₃ to be AlO.
6. The following chemical equation, the decomposition of hydrogen peroxide to water, is not balanced. What must be done to the equation to make it balanced?

2 H₂O₂ (l) → 2 H₂O (l)

1. Change the coefficients from 2 to 1.
2. Add an atom of oxygen to the products.
3. Add a molecule of O₂ to the products.
4. Change the state of matter in the products.
5. Change the subscripts of H₂O to H₂O₂.
6. Which of the following reactions is NOT balanced?
7. 2 Al + 6 HCl → 2 AlCl₃ + 3 H₂
8. Fe₂O₃ + 2 Al → 2 Fe + Al₂O₃
9. C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O
10. C₂H₅OH + O₂ → 2 CO₂ + 3 H₂O
11. CaO + 3 C → CaC₂ + CO
12. Acetylene (C₂H₂) is a small organic molecule used in the industrial preparation of many other molecules and also in welding. Acetylene is made from calcium carbide and water, resulting in acetylene and also calcium hydroxide. Which of the following choices is the correct balanced chemical equation for the preparation of acetylene?
13. CaC₂ + H₂O → CaO + C₂H₂
14. CaC₂ + H₂O → Ca(OH)₂ + C₂H₂
15. CaC₂ + 2 H₂O → Ca(OH)₂ + C₂H₂
16. CaC₂ + 2 H₂O → CaO + C₂H₂ + H₂O
17. 2 CaC₂ + H₂O → Ca(OH)₂ + 2 C₂H₂
18. Pentane (C₅H₁₂) reacts with oxygen gas (O₂) to form carbon dioxide (CO₂) and water (H₂O) according to the following reaction. What is the coefficient for oxygen in the balanced equation?

C₅H₁₂ + _?_ O₂ → _?_ CO₂ + _?_ H₂O

1. 2
2. 4
3. 5
4. 6
5. 8

1. Pentane (C₅H₁₂) reacts with oxygen gas (O₂) to form carbon dioxide (CO₂) and water (H₂O) according to the following reaction. What is the coefficient for carbon dioxide in the balanced equation?

C₅H₁₂ + _?_ O₂ → _?_ CO₂ + _?_ H₂O

1. 2
2. 4
3. 5
4. 6
5. 8
6. Pentane (C₅H₁₂) reacts with oxygen gas (O₂) to form carbon dioxide (CO₂) and water (H₂O) according to the following reaction. What is the coefficient for water in the balanced equation?

C₅H₁₂ + _?_ O₂ → _?_ CO₂ + _?_ H₂O

1. 2
2. 4
3. 5
4. 6
5. 8

1. How many atoms of oxygen are present in the reactants of this chemical equation?

Mg(OH)₂ + 2 HCl → MgCl₂ + 2 H₂O

1. 0
2. 1
3. 2
4. 3
5. 4
6. How many atoms of hydrogen are present in the products of this chemical equation?

Mg(OH)₂ + 2 HCl → MgCl₂ + 2 H₂O

1. 0
2. 1
3. 2
4. 3
5. 4
6. How many atoms of magnesium are present in the reactants of this chemical equation?

Mg(OH)₂ + 2 HCl → MgCl₂ + 2 H₂O

1. 0
2. 1
3. 2
4. 3
5. 4
6. Is this chemical equation balanced?

Mg(OH)₂ + 2 HCl → MgCl₂ + 2 H₂O

1. No. The number of magnesiums in the reactants is different from the number in the products.
2. No. The number of hydrogens in the reactants is different from the number in the products.
3. No. The number of oxygens in the reactants is different from the number in the products.
4. No. The number of chlorines in the reactants is different from the number in the products.
5. Yes. The same number of each type of atom is present in the reactants and products.
6. The balanced chemical equation for the combustion of propane (C₃H₈) is given below. How many grams of carbon dioxide (CO₂) are released when 35 g of propane are burned in the presence of excess oxygen?

C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O

1. 0.80 g
2. 12 g
3. 35 g
4. 105 g
5. 1500 g
6. The steps for performing stoichiometry calculations are diagramed below:

According to these steps, which of the following equations would allow you to calculate the yield of monosaccharides when 28 g of sucrose is broken down as shown in the following equation?

C₁₂H₂₂O₁₁ + H₂O → 2 C₆H₁₂O₆

sucrose monosaccharides

1. The balanced chemical equation for the combustion of butane is given below. How many grams of O₂ are needed to completely react with 5.0 g of butane in a butane lighter?

2 C₄H₁₀ + 13 O₂ → 8 CO₂ + 10 H₂O

1. 0.42 g
2. 2.8 g
3. 6.0 g
4. 9.1 g
5. 18 g
6. A common, over-the-counter antacid is Al(OH)₃. This antacid reacts with gastric juice (HCl) in the stomach, producing AlCl₃ and H₂O. Which of the following equations can be used to correctly determine how much gastric juice (HCl) reacts with an antacid tablet containing 0.25 grams Al(OH)₃?

1. According to the balanced chemical equation below, if you react 3.0 mole of butene with 3.0 mole of hydrogen, how many moles of butane would you expect to get?

CH₃CH=CHCH₃+ H₂ → CH₃CH₂CH₂CH₃

butene butane

molecular weight : 56 g/mole 58 g/mole

1. 0.0 moles
2. 1.0 mole
3. 2.0 moles
4. 3.0 moles
5. 6.0 moles
6. According to the balanced chemical equation below, if you react 3.0 mole of butene with 3.0 mole of hydrogen, how many grams of butane would you expect to get?

CH₃CH=CHCH₃+ H₂ → CH₃CH₂CH₂CH₃

butene butane

molecular weight : 56 g/mole 58 g/mole

1. 0.0 grams
2. 3.0 gram
3. 58 grams
4. 56 grams
5. 170 grams
6. According to the balanced chemical equation below, if, you react 28 grams of butene with excess hydrogen, how many grams of butane would you expect to get?

CH₃CH=CHCH₃+ H₂ → CH₃CH₂CH₂CH₃

butene butane

molecular weight : 56 g/mole 58 g/mole

1. 0.0 g
2. 29 g
3. 58 g
4. 112 g
5. 116 g
6. By moving, breathing, and living, you do work every day. Work requires energy. Where does this energy come from?
7. The energy comes from food; it undergoes chemical reactions in the cells.
8. The energy does not come from anyplace; it is always in our bodies.
9. The energy comes from breaking bonds in food.
10. The energy comes from breaking bonds in food, oxygen, and water.
11. No one really understands where this energy comes from.
12. Which of the following biological molecules are the major nutrients that make up the food that we eat?
13. proteins
14. nucleic acids
15. steroids
16. fats
17. carbohydrates
18. All of these are major nutrients.
19. I, II, IV, and V
20. I and V
21. III, IV, and V
22. I, IV, and V
23. The name for the heat energy released or absorbed in a chemical reaction is
24. energy.
25. endothermic.
26. exothermic.
27. enthalpy.
28. entropy.
29. Combustion reactions are ___________ because products of the reaction are _________ in potential energy than the reactants.
30. endothermic; higher
31. exothermic; higher
32. endothermic; lower
33. exothermic; lower
34. endothermic; the same
35. Which of the following statements describes an endothermic chemical reaction?
36. During photosynthesis, plants harvest light energy in order to drive the synthesis of carbohydrates from CO₂ and H­₂O.
37. A natural gas burner can be used to heat water.
38. Melting an ice cube requires temperatures above freezing.
39. Metabolizing food supplies the body with the energy required to heat ourselves and move.
40. Exposing water to cold temperatures results in freezing.
41. An endothermic reaction is one that
42. releases heat.
43. has no enthalpy.
44. absorbs heat.
45. has reactants higher in energy than products.
46. has a negative enthalpy.
47. Which of the following diagrams illustrates an endothermic reaction?

I II III

1. I and III
2. II and III
3. I and II
4. I only
5. II only
6. Which of the following reactions releases the most heat?

a. b. c. d. e.

1. An exothermic reaction is one that
2. has a positive enthalpy.
3. has no enthalpy.
4. absorbs heat.
5. has products higher in energy than reactants.
6. has a negative enthalpy.
7. In an exothermic reaction, the reactants are higher in energy than the products. What is the meaning of this difference in energy?
8. The products are more stable than the reactants.
9. The reactants have stronger bonds than the products.
10. The reactants have a lower potential energy than the products.
11. The bond energies of the products are less than the bond energies of the reactants.
12. The reactants are more stable than the products.
13. When bonds break, energy is
14. always released.
15. always absorbed.
16. typically released, but sometimes absorbed.
17. typically absorbed, but sometimes released.
18. absorbed half the time and released half the time.
19. Which bonds are broken over the course of this chemical reaction and which bonds are formed?

2 H₂ + O₂ → 2 H₂O

1. Broken: H-H and O-O Formed: O-H
2. Broken: H-H Formed: O-H and O-O
3. Broken: O-O Formed: O-H and H-H
4. Broken: O-H Formed: O-O and H-H
5. Broken: O-H Formed: O-H
6. Which of the following processes that occur over the course of the reaction above gives off heat?

2 H₂ + O₂ → 2 H₂O

1. breaking H-H
2. breaking O-O
3. breaking O-H
4. forming O-H
5. both breaking and forming bonds
6. Which of the following reactions could be described by the energy diagram below?

Reaction progress

Energy

reactants

products

1. 2 CO₂ + 556 kJ→ 2 CO + O₂
2. CH₄ + 2 O₂ → CO₂ + 2 H₂O + heat
3. 8 H₂S + heat → 8 H₂ + S₈
4. 6 CO₂ + 6 H₂O + heat→ C₆H₁₂O₆ + 6 O₂
5. All of the above
6. The enthalpy for the reaction described by the energy diagram below is

Reaction progress

Energy

reactants

products

1. very large.
2. greater than zero, but not necessarily very large.
3. exactly zero.
4. less than zero.
5. It is not possible to predict anything about the enthalpy of this equation.
6. Which statement best describes how the temperature of the surroundings change as a result of the reaction represented by energy diagram below?

Reaction progress

Energy

reactants

products

1. The temperature of the surroundings does not change.
2. The temperature of the surroundings increases.
3. The temperature of the surroundings decreases.
4. The surroundings will become very cold.
5. It is not possible to predict anything about the temperature of the surroundings based on this diagram.
6. The reaction that occurs in a hydrogen fuel cell, shown below, is exothermic. According to the Conservation of Energy, the reverse reaction, called electrolysis,

2H₂ + O₂ → 2H₂O hydrogen fuel cell

2H₂O → 2H₂ + O₂ electrolysis

• 1. is also exothermic.
  2. is endothermic.
  3. does not involve energy.
  4. has an energy change of zero.
  5. involves energy in some way, but it is impossible to determine how.

1. A calorimeter is used to measure the energy content of foods because the energy measurement obtained using a calorimeter is the same as the energy we obtain by eating. Which of the following statements explains why this is the case?
2. They are the same because both the calorimeter and body combust food to obtain only heat energy.
3. They are the same because both the calorimeter and body combust food in a single exothermic step.
4. They are the same because both the calorimeter and body combust food in a complex series of steps.
5. They are the same because, overall, metabolism is a combustion reaction.
6. Actually, they are not the same values.
7. How is the reaction that occurs in a calorimeter different from human metabolism?
8. One is a combustion reaction and the other is not.
9. One occurs in many steps and the other does not.
10. One is exothermic and the other is endothermic.
11. One releases carbon dioxide and the other does not.
12. These reactions are exactly the same.
13. The food that we eat is composed of fats, carbohydrates, and proteins. Select the choice in which each type of food is correctly paired with the number of calories in a gram of that food type.

1. One serving (45 g) of dry wild rice contains 1.5 g of fat, 35 g of carbohydrates, and 5 g of protein. How many Calories does a serving of wild rice contain?
2. 166 Calories
3. 170 Calories
4. 200 Calories
5. 340 Calories
6. 370 Calories
7. One serving of animal crackers (30 g) contains 4.5 g of fat, 22 g of carbohydrates, and 2 g of proteins. Which of the following equations would you use to determine the number of calories in one serving of animal crackers?
8. 4.5 g × 4 Cal/g + 22 g × 9 Cal/g + 2 g × 4 Cal/g
9. 4.5 g × 9 Cal/g + 22 g × 4 Cal/g + 2 g × 4 Cal/g
10. 4.5 g × 4 Cal/g + 22 g × 4 Cal/g + 2 g × 4 Cal/g
11. 4.5 g × 9 Cal/g + 22 g × 9 Cal/g + 2 g × 4 Cal/g
12. 4.5 g × 4 Cal/g + 22 g × 4 Cal/g + 2 g × 9 Cal/g
13. How is a biochemical pathway different than a biochemical reaction?
14. Actually, they are identical.
15. Only pathways occur in cells, not reactions.
16. Only reactions occur in cells, not pathways.
17. Reactions are catabolic and pathways are anabolic.
18. A pathway is a specific sequence of reactions.
19. Metabolism is
20. the breakdown of food.
21. the citric acid cycle.
22. the process by which fat is stored or burned.
23. all catabolic and anabolic pathways in the body.
24. the tendency to gain or lose weight.
25. Which of the following statements best describe catabolic pathways?
26. Catabolic pathways build larger molecules from smaller ones.
27. Overall, catabolic pathways release energy.
28. An example of catabolism is when starch is broken down into smaller units of glucose during digestion.
29. I only
30. II only
31. III only
32. I and II
33. II and III
34. During catabolism of food, heat is released. Where does this energy go?
35. It is turned into heat energy.
36. It is used in movement.
37. It is used to drive additional chemical reactions.
38. It is transferred to ATP.
39. All of the above are possible.
40. During anabolism, heat is absorbed. What does the absorption of heat tell us about the relative energies of the starting small molecules and products of anabolism?
41. The products are lower energy than the reactants.
42. The reactants and products must be the same energy.
43. There is no consistent relationship between heat and the relative energies of the small molecules.
44. The reactants are lower energy than the products.
45. Actually, heat is not absorbed during anabolism.
46. During anabolism, heat is absorbed. What does the absorption of heat tell us about how these reactions occur?
47. These reactions do not usually occur because they require energy.
48. These reactions occur very quickly.
49. These reactions occur very slowly.
50. These reactions are driven by heat releasing chemical reactions.
51. These reactions are not required by the body.
52. Which of the following processes are anabolic?
53. muscle building as a result of steroid use
54. releasing energy from food during the citric acid cycle
55. weight loss as a result of burning fat
56. transferring bond energy from food to ATP
57. All of the above
58. Bond breaking is always endothermic and yet catabolism, the breakdown of nutrients, is an overall exothermic process. How can you reconcile these two statements?
59. Catabolism is an exception to the rule.
60. Bond breaking is not really always endothermic.
61. Endothermic bond breaking is only seen in the laboratory.
62. No one really understands this.
63. Catabolism is the sum of many reactions, including many bond-making reactions.
64. Which of the following molecules is known as the “energy currency of the cell”?
65. DNA
66. adenosine triphosphate
67. citric acid
68. insulin
69. starch
70. An overview of metabolism is shown in the following figure. What does this figure tell us about the energy of catabolism and anabolism?

1. Anabolic reactions occur more quickly than catabolic reactions.
2. Catabolism is exothermic and anabolism is endothermic.
3. Overall, we exert more energy than we consume.
4. Overall, the amount of energy that goes into anabolic processes is the same as is released in catabolic processes.
5. The conservation of energy does not apply to biological systems.
6. Which of the following statements best describes the relationship between enthalpy and reaction rate?
7. There is no readily predictable relationship between enthalpy and reaction rate.
8. Exothermic reactions are always slow.
9. Endothermic reactions are always slow.
10. Enthalpy is always larger than reaction rate.
11. The relationship depends on whether the reaction is endo- or exothermic.
12. Which of the following statements describes reaction rate?
13. Reaction rate is how fast a reaction proceeds.
14. Reaction rate is the quantity of reactants consumed over time.
15. Reaction rate is the quantity of products formed over time.
16. Reaction rate is determined, in part, by activation energy.
17. All of the above
18. In order for a reaction to occur, reactant molecules must collide with sufficient energy to overcome an energy barrier. What is this energy barrier called?
19. enthalpy
20. energy
21. entropy
22. activation energy
23. Any of the above
24. Each of the following figures represents a reaction. Which reaction has the fastest rate?

a. b. c. d. e.

1. How does increasing the temperature of a reaction affect the rate?
2. It slows it down by changing the enthalpy.
3. It speeds it up by raising the activation energy.
4. It slows it down by increasing the activation energy.
5. It speeds it up by increasing the kinetic energy of the molecules.
6. It slows it down by increasing the kinetic energy of the molecules.
7. Why does increasing the concentration of reactants typically increase the rate of a reaction?
8. A higher concentration of reactants means a higher kinetic energy per molecule.
9. A higher concentration of reactants means a lower activation energy.
10. A higher concentration of reactants means that a catalyst has been added.
11. A higher concentration of reactants means a higher activation energy.
12. A higher concentration of reactants means more collisions per amount of time.
13. Which of the following do you expect would increase the rate of a reaction?
14. adding a catalyst
15. decreasing temperature
16. decreasing concentration
17. removing product as it is formed
18. All of the above
19. Which of the following do you expect would decrease the rate of a reaction?
20. adding a catalyst
21. increasing temperature
22. increasing concentration
23. decreasing concentration
24. All of the above
25. Which part of the following energy diagram is changed when a catalyst is added, and how is it changed?

energy

reaction progress

I. reactants

III. products

II.

1. I is higher.
2. II is higher.
3. III is higher.
4. I is lower.
5. II is lower.
6. What are biological catalysts called?
7. proteins
8. nucleic acids
9. enzymes
10. carbohydrates
11. lipids
12. A reaction occurs between the large black spheres and the small grey spheres. Each of the boxes below represents different reaction conditions for that reaction. Which of the given boxes contains the reaction conditions that lead to the fastest reaction?

a. b. c. d. e.

1. Which of the following statements is the best definition of chemical equilibrium?
   1. The point at which the mass of reaction products equals the mass of the reactants.
   2. The point at which forward and reverse reactions proceed at the same rate.
   3. The point at which a reaction is balanced.
   4. The point at which the number of moles of product equals the number of moles of reactants.
   5. Both answers b and d correctly define equilibrium.
2. The following reaction is a reversible reaction. Which of the following statements best describes what it means for this reaction to be reversible?

HCOOH + HOCH₃ HCOOCH₃ + H₂O

1. This reaction only occurs in the reverse direction as written above.
2. All of the reactant molecules react to make product and then all of the product molecules react to make reactants again.
3. Forward and reverse reactions proceed at the same rate.
4. Forward and reverse reactions occur simultaneously.
5. The rate of the reverse reaction is must faster than the rate of the forward reaction.

1. The reaction between acetic acid (CH₃COOH) and methanol (CH₃OH) is given below, followed by a list of changes that could be made to the reaction. Which of these changes will result in the equilibrium shifting to the left?

CH₃COOH + CH₃OH CH₃COOCH₃ + H₂O

Changes that could be made to the solution

• 1. Adding more CH₃COOH
  2. Removing H₂O
  3. Adding more CH₃COOCH₃
  4. Removing CH₃OH

1. All of these changes will result in the equilibrium shifting to the left.
2. Only I will result in the equilibrium shifting to the left.
3. Only IV will result in the equilibrium shifting to the left.
4. I and III will result in the equilibrium shifting to the left.
5. III and IV will result in the equilibrium shifting to the left.
6. An endothermic reaction absorbs heat when it occurs. How can the equilibrium of an endothermic reaction be shifted toward the products?
   1. It is not possible to do this.
   2. Add more products.
   3. Cool down the reaction.
   4. Add a catalyst.
   5. Heat the reaction.
7. Arsenic poisoning is a serious problem in Bangladesh, China, and Chile, resulting from contaminated well water. When arsenic poisoning occurs, arsenic binds to proteins and eventually causes cellular damage. This leads to a variety of symptoms in humans including exhaustion, muscle weakness, organ failure, and cancer. Arsenic poisoning is commonly treated with a drug called dimercaprol (or BAL) that binds arsenic. This process sets up a competing equilibrium within the body. Once arsenic reacts to form a complex with BAL, it can be excreted from the body. How does treatment with BAL affect the equilibrium shown below?

Arsenic-protein complex Arsenic + proteins + BAL Arsenic-BAL complex

1. Adding BAL does not affect the equilibrium.
2. Adding BAL pushes the reaction to the left.
3. Adding BAL pushes the reaction to the right.
4. Adding BAL causes less arsenic-BAL to be made.
5. Adding BAL causes more arsenic-protein complex to be made.
6. Arsenic poisoning is a serious problem in Bangladesh, China, and Chile, resulting from contaminated well water. When arsenic poisoning occurs, arsenic binds to proteins and eventually causes cellular damage. This leads to a variety of symptoms in humans including exhaustion, muscle weakness, organ failure, and cancer. Arsenic poisoning is commonly treated with a drug called dimercaprol (or BAL) that binds arsenic. This process sets up a competing equilibrium within the body. Once arsenic reacts to form a complex with BAL, it can be excreted from the body. How does excretion of the arsenic-BAL complex affect the equilibrium shown below?

Arsenic-protein complex Arsenic + proteins + BAL Arsenic-BAL

1. Excretion of the arsenic-BAL complex does not affect the equilibrium.
2. Excretion of the arsenic-BAL complex causes less of the complex to be made.
3. Excretion of the arsenic-BAL complex causes more arsenic-protein complex to be made.
4. Excretion of the arsenic-BAL complex causes the equilibrium to shift to the right.
5. Excretion of the arsenic-BAL complex causes the equilibrium to shift to the left.

NH₃ + H₂O ⁺NH₄ + ⁻OH

ammonia water ammonium hydroxide

1. The reaction of water with ammonia is shown above. Which of the following substances are present at equilibrium?
2. Ammonia, water, ammonium, and hydroxide are all present at equilibrium.
3. Only ammonia and water are present at equilibrium.
4. Only ammonium and hydroxide are present at equilibrium.
5. Only hydroxide and hydronium are present at equilibrium.
6. It is not possible to say which molecules will be present at equilibrium.
7. The reaction of water with ammonia is shown below. Which of the following statements best describes the concentration of ammonia and ammonium at equilibrium?

NH₃ + H₂O ⁺NH₄ + ⁻OH

ammonia water ammonium hydroxide

1. The concentration of ammonium is increasing.
2. There is no ammonium at equilibrium.
3. Their concentrations are equal.
4. Their concentrations are constant.
5. There is no ammonia at equilibrium.
6. The reaction of water with ammonia is shown below. What will happen if ammonium is added to the solution when it is at equilibrium?

NH₃ + H₂O ⁺NH₄ + ⁻OH

ammonia water ammonium hydroxide

1. Nothing will happen.
2. The result is not predictable.
3. The ammonium will bubble.
4. The equilibrium will shift to the right.
5. The equilibrium will shift to the left.
6. Which of the following statements best describes how calorimetry is used in medicine?
7. Calorimetry is used to feed patients.
8. Calorimetry is used to measure the temperature of a patient.
9. Calorimetry is used to measure the oxygen needs of a patient.
10. Calorimetry is used to assess the caloric needs of a patient.
11. All of the above
12. Which of the following is a potential consequence of misjudging the caloric needs of a patient?
13. malnourishment
14. muscle fatigue
15. respiratory failure
16. coma
17. All of the above
18. How do direct and indirect calorimetry differ?
19. Direct measures food intake and indirect measures energy output.
20. Direct measures energy output and indirect measures food intake.
21. Direct measures energy output and indirect measures oxygen intake.
22. Direct measures oxygen intake and indirect measures energy output.
23. Direct measures oxygen intake and indirect measures oxygen output.
24. Atwater and Rosa built the first human calorimeter in the 1890s. After measuring the energy expenditure and food and oxygen intake of humans, they made a key discovery about the transformation of matter and energy in the human body. What discovery did they make?
25. Amazingly, humans exert more energy than they take in.
26. Humans are inefficient and don’t exert as much energy as they take in.
27. The confirmation of the conservation of energy in human nutrition and energy output.
28. Direct calorimetry is the gold standard for accurate measurement.
29. All of the above
30. What type of calorimetry is the most practical and why?
31. direct calorimetry because it is the most accurate
32. indirect calorimetry because it is the most accurate
33. direct calorimetry because it is portable and less expensive
34. indirect calorimetry because it is portable and less expensive
35. direct and indirect calorimetry are equally practical
36. A spirometer is used in indirect calorimetry. What does a spirometer measure?
37. oxygen
38. carbon dioxide
39. exhaled water
40. body heat
41. food intake
42. Which of the following statements describe how oxygen intake relates to caloric requirements?
43. Oxygen reacts with food to produce energy.
44. The larger the oxygen intake, the higher the energy output.
45. Oxygen is a product of food metabolism.
    1. All of these statements describe the relationship between oxygen intake and caloric requirements.
    2. I and II describe the relationship between oxygen intake and caloric requirements.
    3. II and III describe the relationship between oxygen intake and caloric requirements.
    4. I and III describe the relationship between oxygen intake and caloric requirements.
    5. Only II describes the relationship between oxygen intake and caloric requirements.