Chemistry Chapter 4

The combustion of one mole of propane, C3H8, releases 531 kcal. How much heat is released by the combustion of 4.40 g of propane? a. 53.1 kcal c. 5.31 x 103 kcal b. 531 kcal d. 5.31 x 104 kcal

A

Which of the following compounds has the largest formula weight? a. KCl c. MgF2 b. NaCl d. BF3

A.

When an acid is added to a solution a gas is formed. Which of the following ions might be in the solution? a. CO32- c. SO42- b. OH- d. none of these

A

0.117 moles of a particular substance weighs 21.9 g. What is the molar mass of this substance? a. 187 g c. 0.00534 g b. 187 amu d. 0.00534 amu

A.

The molecular weight of cholesterol is 710 amu. What is the mass of one molecule of cholesterol? a. 1.18 x 10 -21 g c. 710 g b. 0.00141 g d. 8.48 x 1020 g

A.

Given the reaction 2 HgO(s) → 2 Hg(l) + O2(g). What weight of elemental mercury will be obtained by the decomposition of 0.125 moles of HgO. a. 13.5 g c. 27.0 g b. 25.0 g d. 50.0 g

B

Metabolism of one mole of glucose, C6H12O6, releases 670 kcal. How much heat is released by the combustion of 0.300 moles of glucose? a. 186 kcal c. 2.23 x 103 kcal b. 201 kcal d. 2.41 x 103 kcal

B

O2 can be produced by the reaction 2 KClO3(s) → 2 KCl(s) + 3 O2(g). In one experiment 0.312 g of O2 were formed. How much KClO3 was decomposed? a. 0.484 g c. 1.19 g b. 0.797 g d. 1.79 g

B

When solutions of AgNO3 and NaCl react, the balanced molecular equation is: AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq) How much AgCl is produced when 3.10 g of AgNO3 and 3.10 g of NaCl react? a. 1.55 g c. 4.17 g b. 2.62 d. 6.20 g

B

Which of the following is the correct set of integer coefficients for the balanced equation: ___ C3H8(g) + ___O2(g) → ___CO2(g) + ___H2O(g) a. 3, 8, 1, 2 c. 1, 5, 4, 3 b. 1, 5, 3, 4 d. 4, 3, 2, 1

B

Which of the following is true of a balanced chemical reaction? a. In a balanced chemical equation, number of molecules on the reactant side equals the number molecules on the product side. b. In a balanced chemical equation, the number of atoms on the reactant side equals the number of atoms on the product side. c. Both a. and b. are true. d. Both a. and b. are false.

B.

Diethyl ether can be made from ethanol. The reaction is 2 C2H5OH(l) → (C2H5)2O(l) + H2O(l) In one experiment 46.0 g of ethanol yielded 34.7 g of diethyl ether. What was the percent yield in this experiment? a. 62.1% c. 93.8% b. 80.4% d. 97.0%

C

Sodium sulfite, Na2SO3(aq), is added to wine as an antioxidant since it reacts with the oxygen of the air to form sodium sulfate, Na2SO4(aq). Which of the following is the balanced equation for this reaction? a. Na2SO3(aq) + O(g) → Na2SO4(aq) b. Na2SO3(aq) + 2 O(g) → Na2SO4(aq) c. 2 Na2SO3(aq) + O2(g) → 2 Na2SO4(aq) d. Na2SO3(aq) + O2(g) → Na2SO4(aq)

C

When solutions of H2SO4 and NaOH react, the balanced molecular equation is: H2SO4(aq) + 2 NaOH(aq) → Na2SO4(aq) + 2 H2O(l) How much Na2SO4 is obtained when 4.00 g of H2SO4 reacts with 2.00 g of NaOH? a. 0.65 g c. 3.55 g b. 2.98 g d. 4.20 g

C

Which of the following is true of acetate salts and nitrate salts? a. all acetate salts are soluble but all nitrate salts are insoluble b. all nitrate salts are soluble but all acetate salts are insoluble c. all acetate salts and all nitrate salts are soluble d. all acetate salts and all nitrate salts are insoluble

C

A person drinks 1500 g of water, H2O, per day. How many moles is this? a. 0.0120 c. 83.3 b. 8.33 d. 120.0

C.

A serving of a particular fruit dessert contains 20 g of sugar. If all the sugar is sucrose, C12H22O11, how many molecules of sugar are present in this serving? a. 0.0584 c. 3.52 x 1022 b. 17.1 d. 1.03 x 1025

C.

How many molecules are present in a mole of glucose, C6H12O6? a. 6.92 x 10 -26 c. 6.02 x 1023 b. 3.34 x 1021 d. 1.44 x 1025

C.

How many moles of marble, CaCO3, are there in a 275 g piece of marble? a. 4.57 x 10 -22 c. 2.75 b. 0.364 d. 275

C.

When phosphoric acid, H3PO4(aq) , reacts with solid magnesium hydroxide, Mg(OH)2(s), the products are aqueous magnesium phosphate and water. Which of the following is the balanced equation for this reaction? a. H3PO4(aq) + Mg(OH)2(s) → MgPO4(aq) + H2O(l) b. 2 H3PO4(aq) + Mg(OH)2(s) → Mg(PO4)2(aq) + 2 H2O(l) c. 3 H3PO4(aq) + 2 Mg(OH)2(s) → Mg2(PO4)3(aq) + 2 H2O(l) d. 2 H3PO4(aq) + 3 Mg(OH)2(s) → Mg3(PO4)2(aq) + 6 H2O(l)

D

You have a sample of 1.204 x 1024 atoms of gold. How much does this sample weigh? a. 2.00 g c. 197 g b. 98.5 g d. 394 g

D.

Which of the following sulfides is soluble in water? a. Ag2S c. K2S b. FeS d. PbS

B

Given the reaction 2 HgO(s) → 2 Hg(l) + O2(g). What weight of elemental mercury will be obtained by the decomposition of 94.5 g of HgO. a. 43.8 g c. 87.5 g b. 78.5 g d. 175 g

C

The balanced equation for burning octane is: 2 C8H18(g) + 25 O2(g) → 18 H2O(g) + 16 CO2(g) What weight of oxygen is required to completely burn 19.8 g of octane? a. 28.1 g c. 69.5 b. 34.7 d. 139 g

C

Metabolism of one mole of glucose, C6H12O6, releases 670 kcal. How much heat is released by the combustion of 50.0 g of glucose? a. 186 kcal c. 2.23 x 103 kcal b. 201 kcal d. 2.41 x 103 kcal

A

Which of the following is reduction? a. gain of electrons c. gain of oxygen b. loss of hydrogen d. none of these

A

You have a sample of 3.01 x 1023 atoms of silver. How much does this sample weigh? a. 0.0500 g c. 53.9 g b. 2.00 g d. 107.9 g

C.

Ethanol is produced industrially by the acid catalyzed reaction of ethylene with water. The balanced equation for this reaction is: C2H4(g) + H2O(g) → C2H5OH(l) If water is present in excess, how many moles of ethanol can be produced from 7.24 moles of ethylene? a. 7.24 c. 28.0 b. 14.5 d. 46.0

A

The balanced equation N2(g) + 2 O2(g) → 2 NO2(g) means which of the following? a. One mole of nitrogen reacts with two moles of oxygen to form two moles of nitrogen dioxide. b. One gram of nitrogen reacts with two grams of oxygen to form two grams of nitrogen dioxide. c. The equation means both a. and b. d. The equation means Neither a. nor b.

A

When solutions of AgNO3 and NaCl react, the balanced molecular equation is: AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq) How much AgCl is produced when 3.10 g of AgNO3 and 0.600 g of NaCl react? a. 1.47 g c. 2.62 g b. 2.23 g d. 3.70 g

A

When solutions of AgNO3 and NaOH react, the balanced molecular equation is: 2 AgNO3(aq) + 2 NaOH(aq) → Ag2O(s) + 2 NaNO3(aq) + H2O(l) How much Ag2O is produced when 2.00 g of AgNO3 and 0.300 g of NaOH react? a. 0.869 g c. 1.74 g b. 1.43 g d. 2.30 g

A

Which of the following is true about a molecule which contains two polar bonds which have the different degrees of polarity? a. it will always be polar c. it will only be polar if it is bent b. it will never be polar d. it will only be polar if it is linear

A.

Lime, CaO, is produced by the reaction CaCO3(s) → CaO(s) + CO2(g). What weight of CO2 is obtained by the decomposition of 38.7 g of CaCO3? a. 15.5 g c. 21.7 g b. 17.0 g d. 23.2 g

B

Which of the following is the correct set of integer coefficients for the balanced equation: ___ C5H12(g) + ___O2(g) → ___CO2(g) + ___H2O(g) a. 1, 5, 5, 6 c. 5, 1, 8, 6 b. 1, 8, 5, 6 d. 5, 12, 2, 4

B

The mass of an atom of 12C is exactly 12 atomic mass units. Which of the following describes a mole of 12C atoms? a. a sample which weighs exactly 12 atomic mass units b. a sample which contains 6.02 x 1023 atoms of 12C c. both a. and b. d. Neither a. nor b.

B.

What is the formula weight ammonium carbonate, (NH4)2CO3? a. 78.1 amu c. 108.4 amu b. 96.1 amu d. 138.2 amu

B.

What is the molar mass of water, H2O? a. 17.01 g c. 17.01 amu b. 18.02 g d. 18.02 amu

B.

What is the molecular weight of ibuprofen, C13H18O2? a. 29.0 amu c. 289.4 amu b. 206.3 amu d. 377.7 amu

B.

Which of the following is true of a chemical reaction? a. In a chemical reaction, the number of moles of product always equals the number of moles of reactants. b. In a chemical reaction, the mass of the products always equals the mass of the starting materials that have reacted. c. Both a. and b. are true. d. Both a. and b. are false.

B.

Ethyl chloride is prepared by the reaction of ethane with chlorine according to the reaction: 2 C2H6 (g) + Cl2(g) → C2H5Cl(l) + HCl(g) The percent yield of ethyl chloride in one experiment was 96.3% and the actual yield was 74.4 g. How much ethylene did the chemist use in this experiment? a. 35.5 g c. 70.9 g b. 38.7 d. 77.3 g

C

In a blast furnace, coke, which is solid carbon, reacts with O2(g) to form carbon monoxide. The carbon monoxide then reacts with Fe2O3(s) to produce solid iron and carbon dioxide. Which of the following is the balanced equation for this combined process? a. 2 Fe2O3(s) + 3 C(s) + 3 O2(g) → 2 Fe(s) + 3 CO2(g) b. 2 Fe2O3(s) + 2 C(s) + 3 O2(g) → 4 Fe(s) + 2 CO2(g) c. 2 Fe2O3(s) + 6 C(s) + 3 O2(g) → 4 Fe(s) + 6 CO2(g) d. 2 Fe2O3(s) + C(s) + 3 O2(g) → Fe(s) + CO2(g)

C

In the industrial synthesis of acetic acid, methanol is reacted with carbon monoxide. The balanced equation for this reaction is: CH3OH(g) + CO(g) → CH3COOH(l) How many grams of CO(g) are required to produce 16.6 moles of acetic acid? a. 16.6 g c. 465 g b. 33.2 g d. 996 g

C

Lime, CaO, is produced by the reaction CaCO3(s) → CaO(s) + CO2(g). What weight of CaO is obtained by the decomposition of 38.7 g of CaCO3? a. 15.5 g c. 21.7 g b. 17.0 g d. 23.2 g

C

When a solution of ammonium chloride, NH4Cl, is added to a solution of lead(II) nitrate, Pb(NO3)2, a white precipitate of lead chloride, PbCl2, forms. Which of the following is the net ionic equation for this reaction? a. 2 NH4Cl(aq) + Pb(NO3)2(aq) → PbCl2(s) + 2 NH4NO3(aq) b. 2 NH4+(aq) + 2 Cl-(aq) + Pb2+(aq) + 2 NO3-(aq) →PbCl2(s) + 2 NH4+(aq) + 2 NO3-(aq) c. Pb2+(aq) + 2 Cl-(aq) → PbCl2(s) d. Pb2+(aq) + Cl22-(aq) → PbCl2(s)

C

The atomic weight of platinum is less than that of gold. If you have a 10 g sample of each of these metals, which of the following is true? a. You have fewer of atoms of platinum than of gold. b. You have equal numbers of atoms of platinum and gold. c. You have more atoms of platinum than of gold. d. There is insufficient information to determine which of the above is true.

C.

Of the following ions, which always forms soluble compounds? a. Na+ c. C2H3O2- (acetate ion) b. NH4+ d. all of these

D

Which of the following is oxidation? a. loss of electrons b. loss of hydrogen c. gain of oxygen d. all of these

D

Which of the following is reduction? a. gain of electrons c. loss of oxygen b. gain of hydrogen d. all of these

D

Which of the following is the correct set of integer coefficients for the balanced equation: ___ C6H14(g) + ___O2(g) → ___CO2(g) + ___H2O(g) a. 1, 1, 1, 1 c. 1, 9.5, 6, 7 b. 1, 3, 6, 7 d. 2, 19, 12, 14

D

How many hydrogen atoms are there in 2.50 moles of C6H12O6? a. 2.50 c. 1.51 x 1024 b. 12.0 d. 1.81 x 1025

D.

The molar mass of gold is approximately 197 g. What is the approximate mass of one atom of gold? a. 3.06 x 1021 g c. 5.08 x 10 -3 g b. 197 g d. 3.27 x 10 -22 g

D.

What is the formula weight of barium phosphate, Ba3(PO4) 2? a. 232.3 amu c. 559.6 amu b. 537.9 amu d. 601.9 amu

D.