Deck 6: Chemical Reactions: Mole and Mass Relationships

Question 1

How many molecules are present in 3.25 mol of C₂H₆O?

A)3.25 molecules
B)46.0 molecules
C)1.85 × 10²³ molecules
D)6.02 × 10²³ molecules
E)1.96 × 10²⁴ molecules

Answer 1

1.96 × 10²⁴ molecules

Question 2

How many molecules are present in 4.25 mol of CCl₄?

A)9.26 × 10²⁴ molecules
B)2.56 × 10²⁴ molecules
C)653.69 molecules
D)153.81 molecules
E)3.69 × 10^-23 molecules

Answer 2

2.56 × 10²⁴ molecules

Question 3

42.0 g Cl₂ contains ________ molecules Cl₂.

A)1.18
B)3.57 × 10²³
C)6.75 × 10²³
D)1.78 × 10²³
E)0.592

Answer 3

3.57 × 10²³

Question 4

How many molecules are there in 3.00 moles of NH₃?

A)1.00 molecules
B)3.00 molecules
C)17.00 molecules
D)1.20 × 10²⁴ molecules
E)1.81 × 10²⁴ molecules

Question 5

The molecular weight of PCl₃ is ________ amu.

A)66.42
B)136.00
C)137.33
D)139.00
E)199.26

Question 6

The molar mass of Fe(OH)₃ is ________ g.

A)72.86
B)74.88
C)89.87
D)104.86
E)106.87

Question 7

The formula weight of Al₂(SO₄)₃ is ________ grams.

A)214.14
B)278.02
C)315.14
D)342.14
E)450.14

Question 8

A thimble of water contains 4.0 × 10²¹molecules.The number of moles of H₂O is

A)2.4 × 10⁴⁵.
B)6.6 × 10^-3.
C)6.6 × 10^-23.
D)2.4 × 10²³.
E)2.4 × 10^-23.

Question 9

The number of grams in 0.350 mol of Na is

A)0.350.
B)8.05.
C)11.0.
D)23.0.
E)65.7.

Question 10

Acid rain forms in the upper atmosphere by the reaction of sulfur trioxide with water forming sulfuric acid.Calculate the mass in grams of 5.65 × 10²¹ molecules of SO₃.

A)2.72 × 10⁴⁷ g
B)1.17 × 10^-4 g
C)0.751 g
D)0.0751 g
E)1.17 g

Question 11

The formula weight of ammonium carbonate, (NH₄)₂CO₃ is ________ amu.

A)64.11
B)82.10
C)96.09
D)120.13
E)180.17

Question 12

The molar mass of butane,C₄H₁₀,is ________ grams.

A)22.01
B)49.05
C)52.08
D)58.12
E)68.24

Question 13

Which quantity contains Avogadro's number of molecules?

A)8.8 g CO₂
B)34 g of NH₃
C)9 g of H₂O
D)98 g of H₂SO₄
E)73 g of HCl

Question 14

Which statement based on the mole concept is not correct?

A)The molar mass of a diatomic element is its atomic weight in grams times two.
B)The number of atoms in one mole of platinum is the same as the number of atoms in one mole of uranium.
C)One mole of sodium chloride,NaCl,contains the same number of ions as one mole of calcium sulfate,CaSO₄.
D)One mole of methane,CH₄,contains the same number of atoms as one mole of carbon dioxide,CO₂.
E)One mole of bromine,Br₂,contains the same number of molecules as one mole of propane,C₃H₈.

Question 15

Which statement concerning the mole is not correct?

A)The molar mass of any compound is equal to its molecular weight in grams.
B)A mole of metal contains N_A atoms of that metal.
C)A mole of any compound contains one mole of each kind of atom found in that compound.
D)A mole of a diatomic element contains 2 × N_A moles of atoms of the element.
E)All of these statements are correct.

Question 16

If a tablet of acetaminophen,C₈H₉NO₂,weighs 324 mg,how many moles are there in the tablet?

A)2.15 × 10^-3
B)48.9
C)4.89 × 10⁴
D) 2.15
E)466

Question 17

Calculate the number of moles of aspirin,C₉H₈O₄,in 4.0 gram sample.

A)2.2 × 10^-4 moles
B)2.2 moles
C)4.6 × 10^-3 moles
D)0.022 moles
E)180 moles

Question 18

Ammonium sulfate is a common component of fertilizer.Calculate it's formula weight.

A)63.07 amu
B)118.13 amu
C)132.13 amu
D)128.11 amu
E)114.10 amu

Question 19

The formula mass of copper(II)chloride is ________ g.

A)98.90
B)133.00
C)134.45
D)162.53
E)197.80

Question 20

Which statement concerning the mole concept is not true?

A)The molar mass of a metal is its atomic weight expressed in grams.
B)The mole concept makes a connection between the mass of a substance and the number of particles or units of that substance.
C)One mole of any compound contains one mole of atoms.
D)One mole of sodium contains the same number of atoms as one mole of carbon.
E)One mole of water contains the same number of molecules as one mole of ammonia.

Question 21

The number of grams in 2.65 mol of SO₂ is

A)2.65.
B)64.1.
C)24.2.
D)170.
E)1.60 × 10²⁴.

Question 22

In the balanced reaction shown,the mole ratio of Fe₂S₃ to O₂ is
Fe₂S₃ + 4 O₂ → 2 FeO + 3 SO₂

A)5 to 5.
B)1 to 4.
C)4 to 1.
D)1 to 2.
E)4 to 3.

Question 23

How many moles of CO₂ are produced when 2.5 moles of O₂ react according to the following equation?
C₃H₅ + 5 O₂ → 3 CO₂ + 4 H₂O

A)1.5
B)3.0
C)5.0
D)6.0
E)18

Question 24

50.0 g of Cl₂ contains ________ mol Cl₂.

A)50.0
B)1775
C)0.705
D)1.41
E)4.24 × 10²³

Question 25

105 g of MgCl₂ contains ________ mol MgCl₂.

A)105
B)6.62 × 10²³
C)1.10
D)1.76
E)1.06 × 10²⁴

Question 26

Determine the number of moles of water produced when one mole of NH₃ reacts according to the balanced reaction shown.
4 NH₃ + 5 O₂ → 4 NO + 6 H₂O

A)1.00
B)1.25
C)1.50
D)0.67
E)1.33

Question 27

How many moles of NaHCO₃ are present in a 2.00 g sample?

A)2.38 × 10^-2 mol
B)1.27 × 10^-2 mol
C)2.00 mol
D)85.0 mol
E)168 mol

Question 28

Interpret in words the equation shown.
P₄O₁₀(s)+ 6 H₂O(l)→ 4 H₃PO₄(aq)

A)One mole of solid tetraphosphorus decaoxide reacts with six moles of liquid water to produce four moles of phosphoric acid solution.
B)Zero moles of solid phosphoric oxide dissolve in six moles of water to produce four moles of phosphorous acid.
C)One mole of phosphorus(X)oxide combines with six moles of water to produce four moles of solution of hydrogen phosphate.
D)Four moles of solid phosphorus,five moles of diatomic oxygen gas,and six moles of liquid water react together to produce four moles of phosphoric acid in solution.
E)Four atoms of phosphorus,16 atoms of oxygen,and 12 atoms of hydrogen rearrange to produce four molecules of phosphoric acid.

Question 29

In the reaction shown,what is the mole ratio that would be used to determine the number of moles of oxygen needed to react with 3.2 moles of C₄H₁₀?
2 C₄H₁₀+ 13O₂→ 8 CO₂+ 10 H₂O

A)
B)
C)
D)
E)

Question 30

The combustion of propane gas (C₃H₈)is used to fuel barbeque grills.In order to produce 5.65 moles of water how many moles of oxygen gas are needed?
C₃H₈(g)+ 5 O₂(g)→ 3 CO₂(g)+ 4 H₂O(l)

A)3.39 mol
B)4.52 mol
C)7.06 mol
D)1.13 mol
E)1.41 mol

Question 31

How much Ca(NO₃)₂ should be weighed out to have 0.650 mol?

A)66.4 g
B)97.6 g
C)107 g
D)133 g
E)165 g

Question 32

The combustion of propane gas is used to fuel barbeque grills.If 4.65 moles of propane,C₃H₈,are burned in a grilling session,how many moles of carbon dioxide gas are formed?
C₃H₈(g)+ 5 O₂(g)→ 3 CO₂(g)+ 4 H₂O(l)

A)1.55 mol
B)14.0 mol
C)18.6 mol
D)1.16 mol
E)3.49 mol

Question 33

The Haber process is used to make ammonia,which is an important source of nitrogen that can be metabolized by plants.Using the equation below,determine how many moles of ammonia will be formed from 8.55 mole of nitrogen.
N₂(g)+ 3 H₂(g)→ 2 NH₃(g)

A)4.28 mol
B)0.240 mol
C)5.7 mol
D)17.1 mol
E)12.8 mol

Question 34

Consider the reaction N₂(g)+ O₂(g)→ 2 NO(g).

A)How many g NO can be produced when 25.0 g of nitrogen reacts?
B)How many g NO can be produced when 25.0 g of oxygen reacts?
C)Based on your answers in a and b,predict the amount of NO that can be produced when 25.0 g nitrogen is reacted with 25.0 g of oxygen.
D)Explain the reasoning used in part c.

Question 35

In the reaction shown,how many moles of HCl are needed to react with 2.4 moles of Al?
2 Al + 6 HCl → 2 AlCl₃ + 3 H₂

A)0.8
B)1.3
C)4.8
D)6.4
E)7.2

Question 36

In the reaction shown,what is the mole ratio that would be used to determine the number of moles of That would be produced when 3.5 moles of AlC Are produced?
2 Al + 6 HCl → 2 AlC + 3

A)
B)
C)
D)
E)

Question 37

A student weighed 0.550 g of lithium chloride,LiCl,to use in a reaction.How many moles is this?

A)77.08
B)42.39
C)23.31
D)5.11
E)0.0130

Question 38

What does the balanced equation given below mean?
CH₄ + 2 O₂ → CO₂ + 2H₂O

A)One mole of methane reacts with two moles of oxygen to produce one mole of carbon dioxide and two moles of water.
B)One gram of methane reacts with two grams of oxygen to produce one gram of carbon dioxide and two grams of water.
C)One molecule of methane reacts with two molecules of oxygen to produce one molecule of carbon dioxide and two molecules of water.
D)A,B,and C are correct.
E)A and C are correct.

Question 39

The active ingredient in many antacid tablets is calcium carbonate,CaCO₃.How many moles of calcium carbonate are contained in a tablet weighing 550.mg?

A)5.51
B)55.1
C)5.51 × 10^-3
D)5.51 × 10^-4
E)5.51 × 10⁴

Question 40

The number of grams in 7.00 moles of N₂ is

A)7 × (6.02 × 10²³).
B)14.0.
C)28.0.
D)98.0.
E)196.

Question 41

Which is the limiting reactant when 3.00 g of calcium are reacted with 8.00 g of water to produce hydrogen gas in the following equation?
Ca(s)+ 2 H₂O(l)→ Ca(OH)₂(aq)+ H₂(g)

A)Ca
B)H₂O
C)Ca(OH)₂
D)H₂
E)not enough information is given

Question 42

Match the following.
The molar mass of

A)212.4 g
B)219 g
C)225 g
D)208.2 g

Question 43

How many grams of C will be consumed when 5.00 grams of Na₂SO₄ react according to the balanced reaction shown?
Na₂SO₄ + 2 C → Na₂S + 2 CO₂

A)0.038 g
B)0.211 g
C)0.844 g
D)1.69 g
E)17.1 g

Question 44

The fuel for your car is a mixture of octane and several other hydrocarbons.What mass of CO₂ will be produced when 125 g of C₈H₁₈ react completely in the following equation?
2 C₈H₁₈ + 25 O₂ → 16 CO₂ + 18 H₂O

A)6.03 g
B)386 g
C)259 g
D)40.5 g
E)0.199 g

Question 45

Match the following.
The molar mass of BaC

A)212.4 g
B)219 g
C)225 g
D)208.2 g

Question 46

Match the following.
The mass of 1.22 moles of iron(II)nitrate

A)212.4 g
B)219 g
C)225 g
D)208.2 g

Question 47

The percentage yield of a reaction can best be described as the ________ times 100%.

A)amount of product you could make if the reaction went to completion
B)total amount of materials involved in a reaction
C)amount of desired product divided by the amount of unwanted product
D)amount of product obtained divided by the maximum possible amount of product
E)amount of reactants left over divided by the original amounts

Question 48

The reaction N₂ + 3 H₂ → 2 NH₃ is used to produce ammonia.When 450.g of hydrogen was reacted with nitrogen,1575 g of ammonia were produced.What is the percent yield of this reaction?

A)62.1%
B)41.5%
C)30.8%
D)20.7%
E)More information is needed to solve this problem.

Question 49

How many grams of fluorine are required to produce 20.0 grams of FeF₃ from the reaction shown?
2 Fe + 3F₂ → 2 FeF₃

A)4.49 g
B)5.05 g
C)6.74 g
D)10.1 g
E)20.2 g

Question 50

The Haber process is used to make ammonia,which is an important source of nitrogen that can be metabolized by plants.Using the equation below,determine how many kilograms of ammonia will be formed from 89.5 kg of hydrogen.
N₂(g)+ 3H₂(g)→ 2NH₃(g)

A)5.02 × 10⁵ kg
B)1130 kg
C)1.74 kg
D)2050 kg
E)502 kg

Question 51

The following equation represents the formation of nitrogen dioxide,a major component of smog,
2 NO + O₂ → 2 NO₂
If 0.68 mole of NO is reacted with 0.79 mole of O₂ to produce NO₂,the limiting reactant is

A)both NO and O_2.
B)NO.
C)O_2.
D)NO_2.

Question 52

In a reaction to produce chlorine gas,the theoretical yield is 25.6g.What is the actual yield of the reaction if the percent yield is 83.5%?

A)214 g
B)21.4 g
C)3.26 g
D)0.0326 g
E)2.56 g

Question 53

Given the following balanced equation,answer the following:
C₂H₅OH + 3 O₂ → 2 CO₂ + 3 H₂O

A)What is the theoretical yield of carbon dioxide in this reaction if 39.6 g of ethanol is burned in the presence of 54.8 g of oxygen?
B)What is the percent yield for this reaction if the actual amount of carbon dioxide formed is 45.5 grams?

Question 54

In the reaction 2 C + O₂ → 2 CO,how many moles of carbon are needed to produce 66.0 g of carbon monoxide?

A)0.424
B)1.18
C)2.36
D)4.71
E)28.3

Question 55

Match the following.
The mass of 2.25 moles of

A)212.4 g
B)219 g
C)225 g
D)208.2 g

Question 56

In a reaction to produce ammonia,the theoretical yield is 420.g.What is the percent yield if the actual yield is 350.g?

A)20.0%
B)83.3%
C)16.7%
D)120%
E)105%

Question 57

A solution containing 145.0 g AgNO₃ is mixed with a CaCl₂ solution and 98.4 of AgCl is recovered.Calculate the % yield of the reaction.

A)40.16%
B)61.11%
C)61.99%
D)80.44%
E)161.3%