Deck 4: Stoichiometry

Question 1

If: 4C + S₈ → 4CS₂, how many moles of S₈ are required for the formation of 6.75 moles of CS₂?

A) 15.0
B) 13.5
C) 1.69
D) 2.00

Answer 1

1.69

Question 2

If a "classic" SUV features a 52 gallon (197 L) gas tank and assuming complete combustion and a molecular formula of C₈H₁₈ for gasoline, how many L of air are consumed per tank of gasoline. Recall that air is 21% oxygen and assume a density of 0.78 g/mL for gasoline.

A) 300 L
B) 1,600 L
C) 1,000,000 L
D) 1,700,000 L

Answer 2

1,700,000 L

Question 3

Sulfuric acid can be manufactured using the reaction:
2 S( s ) + 3 O₂( g ) + 2 H₂O( l ) → 2 H₂SO₄( aq )
If a manufacturing site consumes 65 metric tons (1 metric ton = 1000 kg) of sulfur with unlimited access to O₂ and H₂O, how many metric tons of sulfuric acid may be produced?

A) 165
B) 233
C) 199
D) 117

Answer 3

199

Question 4

The presence of oxygenates such as MTBE in gasoline result in a more complete combustion and reduced unwanted emissions.

Question 5

Nitroglycerin detonates according to the balanced reaction:
4 C₃H₅N₃O₉( l ) → 12 CO₂( g ) + 6 N₂( g ) + O₂( g )+ 10 H₂O( g ).
If 1.00 kg of nitroglycerin is detonated, how many L of products (assume all gases at standard temperature and pressure, so 1.00 mole = 22.4 L of volume) are released?

A) 107 L
B) 428 L
C) 715 L
D) 1000 L

Question 6

Given the formation of Al₂O₃ from a reaction between aluminum and oxygen, how many moles of the oxide can form using this reaction if 26.2 moles of Al metal react in an unlimited amount of oxygen?

A) 26.2
B) 3.28
C) 13.1
D) 4.91

Question 7

Alkanes contain only carbon, hydrogen, and single bonds.

Question 8

Given that: CH₄ + 2O₂ → CO₂ + 2H₂O, how many moles of carbon dioxide are produced in the complete combustion of 100.0 grams of methane (CH₄)?

A) 6.25
B) 12.5
C) 200
D) 0.321

Question 9

Given that: 3 NO₂( g ) + H₂O( l ) → 2 HNO₃( aq )+ NO( g ), what quantity (L) of NO₂ is required to completely react 125 grams of water. Assume that the gases are at standard temperature and pressure and hence 1.00 mole occupies 22.4 L of volume.

A) 466 L
B) 155 L
C) 311 L
D) 4.82 L

Question 10

If tin reacts with sodium hydroxide according to the reaction:
Sn + NaOH → Na₂SnO₂ + H₂,
How many moles of hydrogen are liberated from the complete reaction of 3.47 × 10⁴ kg of tin metal in excess sodium hydroxide?

A) 3.47 × 10⁷
B) 8.15 × 10⁷
C) 2.47 × 10⁶
D) 2.92 × 10⁵

Question 11

If 4.21 × 10 ^{− 3} moles of Ca²⁺ reacts with excess PO₄^{3 −} to form calcium phosphate, how many moles of the solid will form?

A) 3.04 × 10 ^{− 2}
B) 6.74 × 10 ^{− 3}
C) 1.40 × 10 ^{− 3}
D) 4.21 × 10 ^{− 3}

Question 12

n-Octane is the major component by weight in gasoline

Question 13

Given that: NaClO( aq ) + HCl( aq ) → NaCl( aq ) + HClO( aq ), how many mL of 6.00 M HCl is required to neutralize 25.00 mL of 2.35 M NaClO

A) 9.79 mL
B) 11.7 mL
C) 63.8 mL
D) 117 mL

Question 14

Zinc reacts with oxygen to form ZnO. How many moles of ZnO will form from a reaction of 4.43 moles of Zn and 3.05 moles of oxygen?

A) 3.05
B) 4.43
C) 6.10
D) 9.65

Question 15

The following reaction illustrates the reaction of methanol with oxygen to form carbon dioxide and water:
2 CH₃OH( l ) + 3 O₂( g ) → 2 CO₂( g ) + 4 H₂O( l ).
How many moles of water are produced in a reaction of 15 moles of methanol with 30 moles of oxygen?

A) 20
B) 30
C) 40
D) 50

Question 16

If a 88.2 gram charcoal briquette (assume pure carbon) is burned in an excess of oxygen, what mass of CO₂ is produced by the reaction?

A) 44.1 grams
B) 323 grams
C) 113.8 grams
D) 276 grams

Question 17

Consider: Cl₂O₅ + H₂O → HClO₃. How many moles of HClO₃ are produced from 2.5 moles of Cl₂O₅ reacting with excess water?

A) 1.3
B) 2.5
C) 5.0
D) 6.0

Question 18

Complete combustion of a hydrocarbon mix such as gasoline will yield carbon dioxide and water as the major products.

Question 19

Consider the reaction between NaCl and AgNO₃ to form silver chloride. How much of the insoluble precipitate will be recovered if 582.4 grams of AgNO₃ reacts with excess NaCl?

A) 1.353 kg
B) 491.1 g
C) 257.3 g
D) 810.6 g

Question 20

A limiting reactant is completely consumed in the course of a reaction and may be used to determine how much product(s) may be produced.

Question 21

If 2.5 moles of each of these compounds are burned completely in O₂, which will produce the largest amount of CO₂?

A) C₂H₅OH
B) CH₄
C) C₂H₆
D) C₃H₈

Question 22

Automobile air bags employ a chemical reaction involving the rapid decomposition of sodium azide (NaN₃) into sodium metal and nitrogen gas to inflate in a collision. How much sodium azide is required to decompose to inflate a 20.0 L air bag? Assume that the gas is at standard temperature and pressure, and thus occupies 22.4 L per mole.

A) 76.3 g
B) 42.8 g
C) 38.7 g
D) 62.7 g

Question 23

The titration of 25.00 mL of 0.2215 M HCl required 28.84 mL of NaOH for neutralization. What is the molarity of the NaOH?

A) 0.2555
B) 0.03255
C) 4.004
D) 0.1920

Question 24

Ammonia is manufactured using the reaction:
N₂ + 3 H₂ → 2 NH₃.
How much ammonia can be produced in the reaction of 2.04 × 10 ^{− 3} mol of nitrogen and 6.83 × 10 ^{− 3} mol of hydrogen?

A) 4.08 × 10 ^{− 3} mol
B) 5.20 × 10 ^{− 3} mol
C) 6.83 × 10 ^{− 3} mol
D) 7.47 × 10 ^{− 3} mol

Question 25

A 2.0 L vessel is filled with 7.3 × 10 ^{− 4} mol hydrogen and 6.8 × 10 ^{− 4} mol oxygen. How much water can be produced?

A) 7.3 × 10 ^{− 4} mol
B) 1.4 × 10 ^{− 3} mol
C) 3.7 × 10 ^{− 4} mol
D) 6.6 × 10 ^{− 3} mol

Question 26

An ethanol plant begins a production run with sufficient reactants to predict a theoretical yield of 1250 metric tons of ethanol. The process produces 1178.6 metric tons. What is the percent yield for this production run?

A) 94.29%
B) 82.10%
C) 106.1%
D) 99.23%

Question 27

If liquid mercury and oxygen combine to make mercury(II) oxide, what is the percent yield of HgO if 350.0 grams of Hg( l ) react with 150.0 g of O₂( g ) to produce 272.3 grams of the product?

A) 72.07%
B) 44.03%
C) 13.39%
D) 66.76%

Question 28

A series of ant bites injects 45 μ g of formic acid (HCOOH) into a patient's skin. Considering formic acid is a monoprotic acid (donates one H⁺), how much baking soda (NaHCO₃) is required to neutralize the acid?

A) 458 μ g
B) 54 μ g
C) 135 μ g
D) 82 μ g

Question 29

The Haber process is used to synthesize ammonia from hydrogen and nitrogen. How much hydrogen is required to produce 42.8 kg of ammonia?

A) 56.02 kg
B) 42.8 kg
C) 35.25 kg
D) 7.60 kg

Question 30

A 25.00 mL sample of vinegar is titrated to neutralization with 22.64 mL of 2.00 M NaOH. What is the molarity of the vinegar?

A) 1.66
B) 2.21
C) 2.83
D) 1.81

Question 31

What is the theoretical yield of AgCl if 30.2 mL of 0.1000 M AgNO₃ reacts with an excess of 0.10000 M HCl?

A) 220 mg
B) 433 mg
C) 43.8 mg
D) 915 mg

Question 32

Limestone (CaCO₃) emits CO₂ gas when exposed to HCl. What is the theoretical yield of CO₂ if 9.45 grams of limestone is completely dissolved in HCl?
CaCO₃( s ) + 2 HCl( aq ) → CaCl₂( aq ) + CO₂( g ) + H₂O( l )

A) 21.5 g
B) 4.16 g
C) 9.53 g
D) 24.7 g

Question 33

If 8.42 × 10 ^{− 2} moles of aluminum react with 1.77 × 10 ^{− 2} moles of chlorine gas, how many moles of AlCl₃ may form?

A) 6.50 × 10 ^{− 2}
B) 8.42 × 10 ^{− 2}
C) 1.77 × 10 ^{− 2}
D) 1.18 × 10 ^{− 2}

Question 34

If 60.6 grams of aluminum powder reacts with 125 grams of iron(III)oxide, how much iron metal is recovered?

A) 124.8 g
B) 93.7 g
C) 87.4 g
D) 104.9 g

Question 35

Phosgene is produced in the reaction of carbon monoxide with chlorine gas:
CO( g ) + Cl₂( g ) → COCl₂( g )
What is the theoretical yield of phosgene if 0.767 moles of CO reacts with excess Cl₂ gas?

A) 76.0 g
B) 1.8 × 10 ^{− 2} g
C) 31.9 g
D) 210 mg

Question 36

If 15.00 mL of a 1.00 M HCl solution is mixed with 25.00 mL of a 0.250 M NaOH solution in a process that produces 273 mg of NaCl, what is the percent yield?

A) 19.8%
B) 37.7%
C) 60.0%
D) 74.8%

Question 37

During a tuning test an automobile engine consumes 4.40 × 10 ^{− 3} mol of octane and 5.50 × 10 ^{− 2} mol of oxygen. What condition best describes the fuel mix?

A) too lean (too much oxygen)
B) reasonably correct
C) too rich (too little oxygen)

Question 38

A 118.63 g of SrCl₂ ∙ 6H₂O was heated and 34.81 grams of water were recovered from the sample. What percent of the original H₂O remains in the sample following this heating?

A) 27.61%
B) 38.15%
C) 72.38%
D) 86.19%

Question 39

If 92.8 grams of sodium nitrite are dissolved in 2.3 L of water, the resulting solution has a molarity of:

A) 1.3 M
B) 0.89 M
C) 0.59 M
D) 1.9 M

Question 40

A meat preservation technique requires sodium nitrite. The preservative is prepared by streaming NO( g ) and O₂( g ) through Na₂CO₃( aq ). What is the percent yield for this reaction if the addition of 12.73 g of NO( g ), 16.49 g of O₂( g ), and 35.82 g of Na₂CO₃( aq ) result in the formation of 16.81 g of NaNO₂.
NO( g ) + O₂( g ) + Na₂CO₃( aq ) → NaNO₂( aq ) + CO₂( g )

A) 57.43%
B) 49.51%
C) 58.50%
D) 70.28%