Chapter 6 3 What is the molar mass of nitrogen gas

4) What is the molar mass of nitrogen gas?

A) 14.0 g/mol

B) 28.0 g/mol

C) 6.02 × 1023 g/mol

D) 1.20 × 1023 g/mol

5) What is the mass of a single fluorine molecule, F2?

A) 3.155 × 10-23 g

B) 6.310 × 10-23 g

C) 19.00 g

D) 38.00 g

6) What is the mass of 0.500 mol of dichlorodifluoromethane, CCl2F2?

A) 4.14 × 10-3 g

B) 60.5 g

C) 121 g

D) 242 g

7) How many moles are there in 3.00 g of ethanol, CH3CH2OH?

A) 0.00725 mol

B) 0.0652 mol

C) 15.3 mol

D) 138 mol

8) How many Fe(II) ions are there in 20.0 g of FeSO4?

A) 2.19 × 10-25 iron(II) ions

B) 7.92 × 1022 iron(II) ions

C) 4.57 × 1024 iron(II) ions

D) 1.82 × 1027 iron(II) ions

9) What is the mass of 8.50 x 1022 molecules of NH3?

A) 0.00829 g

B) 0.417 g

C) 2.40 g

D) 121 g

10) How many oxygen atoms are there in 7.00 g of sodium dichromate, Na2Cr2O7?

A) 0.187 oxygen atoms

B) 2.30 × 1021 oxygen atoms

C) 1.60 × 1022 oxygen atoms

D) 1.13 × 1023 oxygen atoms

11) How many chloride ions are there in 4.50 mol of aluminum chloride?

A) 3.00 chloride ions

B) 13.5 chloride ions

C) 2.71 × 1024 chloride ions

D) 8.13 × 1024 chloride ions

12) What is the molar mass of 1-butene if 5.38 × 1016 molecules of 1-butene weigh 5.00 μg?

A) 56.0 g/mol

B) 178 g/mol

C) 224 g/mol

D) 447 g/mol

13) What mass of carbon dioxide, C O2, contains the same number of molecules as 3.00 g of

trichlorofluoromethane, CCl3F?

A) 0.106 g

B) 0.961 g

C) 1.04 g

D) 9.37 g

14) What mass of phosphorus pentafluoride, PF5, has the same number of fluorine atoms as 25.0

g of oxygen difluoride, OF2?

A) 0.933 g

B) 10.0 g

C) 23.3 g

D) 146 g

15) How many anions are there in 2.50 g of MgBr2?

A) 8.18 × 1021 anions

B) 1.64 × 1022 anions

C) 4.43 × 1025 anions

D) 8.87 × 1025 anions

16) How many cations are there in 10.0 g of sodium phosphate?

A) 3.67 × 1022 cations

B) 1.10 × 1023 cations

C) 9.87 × 1024 cations

D) 2.96 × 1025 cations

17) Which of the following has the greatest mass?

A) 3.88 × 1022 molecules of O2

B) 1.00 g of O2

C) 0.0312 mol of O2

D) All of the above have the same mass.

18) Which of the following has the smallest mass?

A) 3.50 × 1023 molecules of I2

B) 85.0 g of Cl2

C) 2.50 mol of F2

D) 0.050 kg of Br2

19) How many moles of CuO can be produced from 0.900 mol of Cu2O in the following

reaction?

2 Cu2O(s) + O2(g) → 4 CuO(s)

A) 0.450 mol

B) 0.900 mol

C) 1.80 mol

D) 3.60 mol

20) How many moles of BCl3 are needed to produce 10.0 g of HCl(aq) in the following

reaction?

BCl3(g) + 3 H2O(l) → 3 HCl(aq) + B(OH)3(aq)

A) 0.0914 mol

B) 0.274 mol

C) 0.823 mol

D) 10.9 mol

21) How many grams of calcium chloride are needed to produce 1.50 g of potassium chloride?

CaCl2(aq) + K2CO3(aq) → 2 KCl(aq) + CaCO3(aq)

A) 0.896 g

B) 1.12 g

C) 2.23 g

D) 4.47 g

22) Balance the chemical equation given below, and determine the number of moles of iodine

that reacts with 30.0 g of aluminum.

________ Al(s) + ________ I2(s) → ________ Al2I6(s)

A) 0.741 mol

B) 1.67 mol

C) 2.22 mol

D) 3.33 mol

23) Balance the chemical equation given below, and determine the number of grams of MgO are

needed to produce 10.0 g of Fe2O3 .

________ MgO(s) + ________ Fe(s) → ________ Fe2O3(s) + ________ Mg(s)

A) 0.312 g

B) 0.841 g

C) 2.52 g

D) 7.57 g

24) Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas. How many

grams of oxygen are formed when 10.0 g of dinitrogen monoxide decomposes?

A) 0.275 g

B) 3.64 g

C) 7.27 g

D) 14.5 g

25) If the density of ethanol, C2H5OH, is 0.789 g/mL. How many milliliters of ethanol are

needed to produce 15.0 g of CO2 according to the following chemical equation?

C2H5OH(l) + 3 O2(g) → 2 CO2(g) + 3 H2O(l)

A) 6.19 mL

B) 9.95 mL

C) 19.9 mL

D) 39.8 mL

26) When 11.0 g of calcium metal is reacted with water, 5.00 g of calcium hydroxide is

produced. Using the following balanced equation, calculate the percent yield for the reaction?

Ca(s) + 2 H2O(l) → Ca(OH)2(aq) + H2(g)

A) 12.3%

B) 24.6%

C) 45.5%

D) 84.0%

27) If the percent yield for the following reaction is 65.0%, how many grams of KClO3 are

needed to produce 32.0 g of O2?

2 KClO3(s) → 2 KCl(s) + 3 O2(g)

A) 53.1 g

B) 81.7 g

C) 126 g

D) 283 g

28) If the percent yield for the following reaction is 75.0%, and 45.0 g of NO2 are consumed in

the reaction, how many grams of nitric acid, HNO3(aq) are produced?

3 NO2(g) + H2O(l) → 2 HNO3(aq) + NO(g)

A) 30.8 g

B) 41.1 g

C) 54.8 g

D) 69.3 g

29) 7.0 g of nitrogen is reacted with 5.0 g of hydrogen to produce ammonia according to the

chemical equation shown below. Which one of the following statements is false?

N2(g) + 3 H2(g) → 2 NH3(g)

A) 3.5 g of hydrogen are left over.

B) Hydrogen is the excess reactant.

C) Nitrogen is the limiting reactant.

D) The theoretical yield of ammonia is 15 g.

30) 5.0 g of iron is reacted with 5.0 g of water according to the chemical equation shown below.

Which one of the following statements is false?

3 Fe(s) + 4 H2O(l) → Fe3O4(s) + 4 H2(g)

A) 6.91 g of Fe3O4 are produced.

B) 2.85 g of H2O are left over.

C) Mass is conserved in this reaction.

D) Water is the limiting reactant.

31) Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and

4.0 g of sodium hydroxide according to the following chemical equation:

2 S(s) + 3 O2(g) + 4 NaOH(aq) → 2 Na2SO4(aq) + 2 H2O(l)

A) S(s)

B) O2(g)

C) NaOH(aq)

D) None of these substances is the limiting reactant.

32) When 7.00 × 1022 molecules of ammonia react with 6.00 × 1022 molecules of oxygen

according to the chemical equation shown below, how many grams of nitrogen gas are

produced?

4 NH3(g) + 3 O2(g) → 2 N2(g) + 6 H2O(g)

A) 1.63 g

B) 1.86 g

C) 4.19 g

D) 6.51 g

47

33) When silver nitrate reacts with barium chloride, silver chloride and barium nitrate are

formed. How many grams of silver chloride are formed when 10.0 g of silver nitrate reacts with

15.0 g of barium chloride?

A) 8.44 g

B) 9.40 g

C) 11.9 g

D) 18.8 g

34) Balance the chemical equation given below, and calculate the volume of nitrogen monoxide

gas produced when 8.00 g of ammonia is reacted with 12.0 g of oxygen at 25°C? The density of

nitrogen monoxide at 25°C is 1.23 g/L.

________ NH3(g) + ________ O2(g) → ________ NO(g) + ________ H2O(l)

A) 11.2 L

B) 16.1 L

C) 11.5 L

D) 17.3 L

35) What is the concentration of FeCl3 in a solution prepared by dissolving 20.0 g of FeCl3 in

enough water to make 275 mL of solution?

A) 4.48 × 10-4 M

B) 0.448 M

C) 2.23 M

D) 2.23 × 103 M

36) How many grams of AgNO3 are needed to make 250. mL of a solution that is 0.135 M?

A) 0.0917 g

B) 0.174 g

C) 5.73 g

D) 91.7 g

37) What volume of a 0.540 M NaOH solution contains 11.5 g of NaOH?

A) 0.155 L

B) 0.532 L

C) 1.88 L

D) 6.44 L

38) What is the concentration of NO3– ions in a solution prepared by dissolving 25.0 g of

Ca(NO3)2 in enough water to produce 300. mL of solution?

A) 0.254 M

B) 0.508 M

C) 0.672 M

D) 1.02 M

39) If the reaction of phosphate ion with water is ignored, what is the total concentration of ions

in a solution prepared by dissolving 3.00 g of K3PO4 in enough water to make 350. mL of

solution?

A) 0.0101 M

B) 0.0404 M

C) 0.162 M

D) 0.323 M

40) What is the concentration of an AlCl3 solution if 150. mL of the solution contains 450. mg of

Cl– ion?

A) 2.82 × 10-2 M

B) 6.75 × 10-2 M

C) 8.46 × 10-2 M

D) 2.54 × 10-1 M

41) What is the concentration of HCl in the final solution when 65 mL of a 12 M HCl solution is

diluted with pure water to a total volume of 0.15 L?

A) 2.8 × 10-2 M

B) 5.2 M

C) 28 M

D) 5.2 × 103 M

42) How many milliliters of a 9.0 M H2SO4 solution are needed to make 0.35 L of a 3.5 M

solution?

A) 0.14 mL

B) 0.90 mL

C) 140 mL

D) 900 mL

43) How many mL of a 0.175 M FeCl3 solution are needed to make 450. mL of a solution that

is 0.300 M in Cl– ion?

A) 0.771 mL

B) 257 mL

C) 771 mL

D) It is not possible to make a more concentrated solution from a less concentrated solution.

44) A student dissolved 4.00 g of Co(NO3)2 in enough water to make 100. mL of stock solution.

He took 4.00 mL of the stock solution and then diluted it with water to give 275. mL of a final

solution. How many grams of NO3– ion are there in the final solution?

A) 0.0197 g

B) 0.0394 g

C) 0.0542 g

D) 0.108 g

45) A student prepared a stock solution by dissolving 10.0 g of KOH in enough water to make

150. mL of solution. She then took 15.0 mL of the stock solution and diluted it with enough

water to make water to make 65.0 mL of a final solution. What is the concentration of KOH for

the final solution?

A) 0.274 M

B) 0.356 M

C) 2.81 M

D) 3.65 M

46) How many milliliters of 0.260 M Na2S are needed to react with 40.00 mL of 0.315 M

AgNO3?

Na2S(aq) + 2 AgNO3(aq) → 2 NaNO3(aq) + Ag2S(s)

A) 24.2 mL

B) 48.5 mL

C) 66.0 mL

D) 96.9 mL

47) How many grams of CaCl2 are formed when 15.00 mL of 0.00237 M Ca(OH)2 reacts with

excess Cl2 gas?

2 Ca(OH)2(aq) + 2 Cl2(g) → Ca(OCl)2(aq) + CaCl2(aq) + 2 H2O(l)

A) 0.00197 g

B) 0.00394 g

C) 0.00789 g

D) 0.0507 g

48) When 31.2 mL of 0.500 M AgNO3 is added to 25.0 mL of 0.300 M NH4Cl, how many

grams of AgCl are formed?

AgNO3(aq) + NH4Cl(aq) → AgCl(s) + NH4NO3(aq)

A) 1.07 g

B) 2.24 g

C) 3.31 g

D) 6.44 g

49) How many milliliters of 0.200 M FeCl3 are needed to react with an excess of Na2S to

produce 1.38 g of Fe2S3 if the percent yield for the reaction is 65.0%?

3 Na2S(aq) + 2 FeCl3(aq) → Fe2S3(s) + 6 NaCl(aq)

A) 25.5 mL

B) 43.1 mL

C) 51.1 mL

D) 102 mL

50) If 100. mL of 0.400 M Na2SO4 is added to 200. mL of 0.600 M NaCl, what is the

concentration of Na+ ions in the final solution? Assume that the volumes are additive.

A) 0.534 M

B) 0.667 M

C) 1.00 M

D) 1.40 M

51) How many milliliters of 0.550 M hydriodic acid are needed to react with 15.00 mL of 0.217

M CsOH?

HI(aq) + CsOH(aq) → CsI(aq) + H2O(l)

A) 0.0263 mL

B) 0.169 mL

C) 5.92 mL

D) 38.0 mL

52) In an acid-base neutralization reaction 38.74 mL of 0.500 M potassium hydroxide reacts with

50.00 mL of sulfuric acid solution. What is the concentration of the H2SO4 solution?

A) 0.194 M

B) 0.387 M

C) 0.775 M

D) 1.29 M

53) Balance the chemical equation given below, and determine the number of milliliters of

0.00300 M phosphoric acid required to neutralize 45.00 mL of 0.00150 M calcium hydroxide.

______ Ca(OH)2(aq) + ______ H3PO4(aq) → ______ Ca3(PO4)2(aq) + ______ H2O(l)

A) 3.04 mL

B) 15.0 mL

C) 22.5 mL

D) 33.8 mL

54) When 280. mL of 1.50 × 10-4 M hydrochloric acid is added to 125 mL of 1.75 × 10-4 M

Mg(OH)2, the resulting solution will be

A) acidic.

B) basic

C) neutral.

D) It is impossible to tell from the information given.

55) Which one of the following contains 39% carbon by mass?

A) C2H2

B) CH4

C) CH3NH2

D) CO2

56) What is the empirical formula of a substance that contains 2.64 g of C, 0.444 g of H, and

3.52 g of O?

A) C H2O

B) C2H4O2

C) C2H4O3

D) C3H4O4

57) Which one of the following is not an empirical formula?

A) CHO

B) CH2O

C) C2H4O

D) C2H4O2

58) Combustion analysis of an unknown compound containing only carbon and hydrogen

produced 0.2845 g of CO2 and 0.1451 g of H2O. What is the empirical formula of the

compound?

A) CH2

B) C2H5

C) C4H10

D) C5H2

59) Combustion analysis of 1.200 g of an unknown compound containing carbon, hydrogen, and

oxygen produced 2.086 g of CO2 and 1.134 g of H2O. What is the empirical formula of the

compound?

A) C2H5O

B) C2H5O2

C) C2H10O3

D) C3H8O2

1) A balanced equation has the same numbers and kinds of ________ on both sides of the

reaction arrow.

2) When the reaction C4H10 + O2 → CO2 + H2O is balanced using the smallest whole number

coefficients, the coefficient in front of O2 is ________.

3) To the nearest whole number, the molar mass of Cu(NO3)2 is ________ g/mol.

4) How many moles are in 7.8 g of acetamide, CH3CONH2?

5) The balanced equation for the gaseous state oxidation of ammonia is shown below.

4 NH3 + 5 O2 → 4 NO + 6 H2O

How many moles of O2 are required to react with 1.2 mole of NH3?

6) The balanced equation for the decomposition of water is shown below.

2 H2O → 2 H2 + O2

If 0.72 g of water react completely in this reaction, what is the theoretical yield of H2?

7) If 4.0 g of H2 react with 4.0 g of F2 in the reaction shown below, what is the limiting

reactant?

H2 + F2 → 2 HF

8) What is the molarity of a solution prepared by dissolving 0.80 g of NaOH in enough water to

make 250 mL of solution?

9) What is the molarity of a solution prepared by diluting 25 mL of 2.0 M HCl with enough

water to make 250 mL of solution?

10) What is the empirical formula of benzene, C6H6?