Deck 4: Calculations, chemical Changes, and the Chemical Equation

Question 1

One mole of any substance contains Avogadro's number of particles of that substance.What is the numerical value of Avogadro's number?

A)6.022 ×10⁻²³
B)1.00 ×10⁻¹⁴
C)12.01
D)1.661 ×10⁻²⁴
E)6.022 × 1023

Answer 1

6.022 × 1023

Question 2

Which notation properly indicates how two molecules of diatomic oxygen would be represented in a chemical equation?

A)(O₂)₂
B)O₄
C)2O₂
D)O₂O₂
E)All of the choices are correct.

Answer 2

2O₂

Question 3

Hydrogen fluoride will react with glass (silicon dioxide,SiO₂)according to the equation below.What mass of HF is required to react completely with 16.0 g of glass?[Molar masses: Si,28.09 g/mol; F,19.00 g/mol; H,1.01 g/mol; O,16.00 g/mol] 4HF(g)+ SiO₂(s)→ SiF₄(g)+ 2H₂O(g)

A)5.33 g
B)21.3 g
C)64.0 g
D)80.0 g
E)320 g

Answer 3

21.3 g

Question 4

Aluminum metal and oxygen gas are produced when aluminum oxide is heated at high temperature.Which statement concerning this chemical change is true?

A)Aluminum oxide is the product in this reaction.
B)This reaction is a neutralization reaction.
C)Aluminum and oxygen are the reactants in this reaction.
D)This reaction is a decomposition reaction.
E)The chemical equation for this reaction is: AlO₂(s)→ Al(s)+ O₂(g).

Question 5

The chemical equation below is unbalanced.What is the coefficient of water when the equation is balanced? Mg(OH)₂(s)+ HCl(g)→ MgCl₂(s)+ H₂O(l)

A)1
B)2
C)3
D)4
E)No coefficient would be shown.

Question 6

What is the mass of 4.00 moles of helium,the gas commonly used to fill party balloons and lighter-than-air ships?

A)4 amu
B)4.00 g
C)8.00 g
D)16.0 g
E)2.41 × 10²⁴ g

Question 7

Which symbol,often found in chemical equations,indicates that a substance is dissolved in water?

A)(w)
B)(l)
C)(aq)
D)(d)
E)(_∆)

Question 8

Which statement best describes the Law of Conservation of Mass?

A)The masses of the reactants in a chemical reaction are always equal.
B)The mass of the product formed in a chemical reaction is determined by the limiting reactant.
C)The mass of the product formed in a chemical reaction is equal to the mass of the reactant in the smallest amount.
D)Matter is neither gained nor lost in a chemical reaction.
E)When two or more products are formed in a chemical reaction,their masses will always be equal.

Question 9

The mass of one atom of oxygen is 16.00 amu.What is the mass of one mole of elemental oxygen (O₂)?

A)32.00 amu
B)32.00 g
C)9.64 × 10²⁴ g
D)1.93 × 10²⁵ g
E)1.88 × 10²² g

Question 10

Which has the greatest mass,one atom of carbon,one atom of hydrogen,or one atom of lithium?

A)one atom of carbon
B)one atom of hydrogen
C)one atom of lithium
D)All three atoms have the same mass.
E)It is impossible to determine.

Question 11

Upon mixing a clear colorless BaCl₂ solution with a clear,colorless Na₂SO₄ solution according to the reaction below,a student observes a white cloudiness form.What is responsible for the cloudiness that is observed? BaCl₂(aq)+ Na₂SO₄(aq)→ BaSO₄(s)+ 2NaCl(aq)

A)NaCl
B)BaSO₄
C)BaCl₂
D)Na₂SO₄
E)It is impossible to tell without doing the reaction oneself.

Question 12

Glucose (C₆H₁₂O₆)is an important energy-rich compound produced by photosynthesis according to the equation below.What mass of glucose can be produced from 2.61 mol of CO₂ and the necessary water? [Molar masses: C,12.01 g/mol; H,1.01 g/mol; O,16.00 g/mol] 6CO₂(g)+ 6H₂O(l)→ C₆H₁₂O₆(l)+ 6O₂(g)

A)0.0128 g
B)0.0869 g
C)69.0 g
D)78.4 g
E)414 g

Question 13

Consider the chemical equation shown below.How many moles of oxygen gas are needed to react with hydrogen to form one mole of water? 2H₂(g)+ O₂(g)→ 2H₂O(l)

A)0.5 mol
B)1 mol
C)3 mol
D)4 mol
E)5 mol

Question 14

The chemical equation below is not balanced.Balance the equation,then determine which statement concerning the balanced equation is TRUE. KClO₃(s)→ KCl(s)+ O₂(g)

A)The balanced equation will have an equal number of moles of reactants and products.
B)The balanced equation will have three atoms of oxygen on each side.
C)The balanced equation will have one atom of potassium on each side.
D)The balanced equation will have two atoms of chlorine on each side.
E)The balanced equation will contain a substance whose coefficient is 1.

Question 15

The unbalanced equation for the combustion of octane,a component of gasoline,is shown below.What would be the coefficient of carbon dioxide once the equation is balanced? C₈H₁₈(l)+ O₂(g)→ CO₂(g)+ H₂O(l)

A)8
B)25
C)16
D)18
E)No coefficient would be shown.

Question 16

What is the mass of one mole of diatomic hydrogen,H₂?

A)1.01 amu
B)2.02 amu
C)1.01 g
D)2.02 g
E)6.022 × 10²³ g

Question 17

A sample of aluminum contains 2.91 × 10²² atoms of aluminum.What is the mass of this sample? [Molar mass: Al,26.98 g/mol]

A)0.767 g
B)1.30 g
C)558 g
D)1.08 × 10²¹ g
E)7.85 × 10²³g

Question 18

What is the general term for the process in which one or more electrons are transferred from one reactant to another?

A)oxidation-reduction
B)neutralization
C)condensation
D)Lewis base
E)decomposition

Question 19

Consider the two beakers labeled A and B.Beaker A contains 1 mole of iron atoms,and Beaker B contains 1 mole of lead atoms.Which statement concerning these samples is known with certainty?

A)Beakers A and B contain an equal number of atoms.
B)Beakers A and B contain equal masses of atoms.
C)Beakers A and B contain an equal volume of atoms.
D)Beakers A and B contain samples with the same density.
E)None of these are correct.

Question 20

How many molecules of water are present in a 5.65 mole sample of water?

A)4.00 × 10²⁴ molecules
B)1.07 × 10²³ molecules
C)3.40 × 10²⁴ molecules
D)9.39 × 10⁻²⁴ molecules
E)4.00 × 10²⁵ molecules

Question 21

Iron reacts with oxygen to form iron(III)oxide according to the chemical equation below.What is the theoretical yield of product when 5.00 grams of Fe react with excess O₂? [Molar masses: Fe,55.85 g/mol; O,16.00g/mol] 4Fe(s)+ 3O₂(g)→ 2Fe₂O₃(s)

A)13.1 g
B)6.53 g
C)7.15 g
D)2.50 g
E)70.5 g

Question 22

Magnesium hydroxide,Mg(OH)₂,as "Milk of Magnesia" can be used to neutralize excess stomach acid,represented by HCl(aq)according to the chemical equation below. Mg(OH)₂(s)+ 2HCl(aq)→ MgCl₂(aq)+ 2H₂O(l)
When 5.00 g of HCl are combined with an excess of Mg(OH)₂,what mass of MgCl₂ can be produced? [Molar masses: H,1.01 g/mol; O,16.00 g/mol; Mg,24.31 g/mol; Cl,35.45 g/mol]

A)13.1 g
B)6.53 g
C)0.957 g
D)2.50 g
E)70.5 g

Question 23

Cisplatin is a chlorine-containing chemotherapy agent with the formula Pt(NH₃)₂Cl₂.What is the mass of one mole of cisplatin?

A)283.02 g/mol
B)286.05 g/mol
C)300.06 g/mol
D)488.91 g/mol
E)492.37 g/mol

Question 24

The fluoride rinse in dental offices usually contains sodium fluoride.Sodium fluoride can be prepared from the reaction between sodium metal and fluorine gas.Which of the following properly represents the balanced chemical equation for this reaction?

A)Na(s)+ F₂(g)→ NaF₂(s)
B)Na(s)+ F(g)→ NaF(s)
C)7Na(s)+ F(g)→ Na₇F(s)
D)2Na(s)+ F₂(g)→ 2Na₂F(s)
E)2Na(s)+ F₂(g)→ 2NaF(s)

Question 25

To convert a given number of moles into the number of atoms,one would multiply by which of the following factors?

A)6.022 × 10²³ atoms/1 mol
B)1 mol/6.022 × 10²³ atoms
C)1.66 × 10^-24 atoms/1 mol
D)1 mol/1.66 × 10^-24 atoms
E)molar mass

Question 26

What is the mass of one mole of carbon atoms?

A)6.022 g
B)12.01 g
C)7.232 g
D)6.022 × 10²³ g
E)7.232 × 10²⁴ g

Question 27

The average mass of one atom of copper is 63.55 amu.What is the mass of Avogadro's number of copper atoms?

A)3.827 × 10²⁵ amu
B)63.55 g
C)3.827 × 10²⁵ g
D)63.55 atoms
E)63.55 formula units

Question 28

A sample of sulfur contains 1.81 × 10²⁴ atoms of sulfur.How many moles of sulfur does this represent?

A)1.81 mol
B)3.01 mol
C)0.333 mol
D)1.09 mol
E)1.77 mol

Question 29

What is the mass of 3.01 mol of sulfur atoms?

A)1.81 × 10²⁴ g
B)32.06 g
C)3.01 g
D)0.150 g
E)96.5 g

Question 30

When the equation below is balanced with the lowest possible whole number coefficients,what is the sum of the coefficients? Ca(s)+ HCl(g)→ CaCl₂(s)+ H₂(g)

A)2
B)4
C)5
D)8
E)10

Question 31

Dinitrogen monoxide,or laughing gas (N₂O),is used as a dental anesthetic and as an aerosol propellant.How many molecules of N₂O are present in a 12.6 g sample of the compound?

A)1.72 × 10²³ molecules
B)1.289 molecules
C)3.34 × 10²⁶ molecules
D)7.59 × 10²⁴ molecules
E)5.14 × 10²³ molecules

Question 32

How many atoms of sulfur are present in a 155 g sample of sulfur? [Molar mass: S,32.06 g/mol]

A)2.91 × 10²⁴ atoms
B)6.02 × 10²³ atoms
C)3.01 × 10²³ atoms
D)2.91 × 10²³ atoms
E)2.01 × 10²³ atoms

Question 33

How is the reaction shown below best classified? 2HgO(s)→ 2Hg(l)+ O₂(g)

A)decomposition
B)combination
C)single-replacement
D)double-replacement
E)acid-base reaction

Question 34

What mass of sodium hydroxide is necessary to react with a solution containing 73.00 g HCl,according to the chemical equation below? [Molar masses: NaOH,39.99 g/mol; HCl,36.45 g/mol] NaOH(aq)+ HCl(aq)→ NaCl(aq)+ H₂O(l)

A)80.09 g
B)66.54 g
C)39.99 g
D)1.850 g
E)7.445 g

Question 35

How is the reaction shown below best classified? 2NaCl(s)+ F₂(g)→ 2NaF(s)+ Cl₂(g)

A)decomposition
B)combination
C)single-replacement
D)double-replacement
E)precipitation

Question 36

How is the reaction shown below best classified? Ca(s)+ 2HCl(aq)→ CaCl₂(g)+ H₂(g)

A)decomposition
B)combination
C)single-replacement
D)double-replacement
E)precipitation

Question 37

Diamond is a pure form of the element carbon.If a 2 carat diamond has a mass of 0.396 g,how many carbon atoms are contained in this diamond?

A)3.97 × 10²² atoms
B)6.58 × 10⁻²⁵ atoms
C)1.99 × 10²³ atoms
D)1.99 × 10²² atoms
E)2.38 × 10²³ atoms

Question 38

How many moles of Au atoms are present in one ounce of pure gold? [1 oz = 28.4 g]

A)1.97 × 10² mol
B)6.94 mol
C)0.144 mol
D)0.0721 mol
E)5.08 × 10^-3 mol

Question 39

What is the mass of a 0.150 mole sample of sulfur?

A)5.17 g
B)4.68 g
C)214 g
D)0.208 g
E)4.81 g

Question 40

Lithium oxide can be produced by the reaction shown below.If a manufacturing company wants to make 25.0 g of Li₂O,what mass of Li is necessary? [Molar masses: Li,6.94 g/mol; O,16.00 g/mol] 4Li(s)+ O₂(g)→ 2Li₂O(s)

A)0.0861 g Li
B)2.903 g Li
C)11.6 g Li
D)12.5 g Li
E)23.2 g Li

Question 41

The chemical equation below is not balanced.What is the coefficient of iron when the equation is balanced with smallest whole number coefficients? Fe(s)+ O₂(g)→ Fe₂O₃(s)

A)1
B)2
C)3
D)4
E)8

Question 42

Classify the following reaction: H₂SO₄(aq)+ 2KOH(aq)→ K₂SO₄(aq)+ 2H₂O(aq)

A)precipitation
B)acid - base
C)oxidation - reduction
D)decomposition
E)combustion

Question 43

What is the formula mass of carbon dioxide? [Atomic masses: C,12.01 amu; O,16.00 amu]

A)28.01 amu
B)28.01 g
C)44.01 amu
D)44.01 g
E)44.01 mol

Question 44

Aspirin is the common name for acetyl salicylic acid,C₉H₈O₄.One tablet contains 0.325 g of aspirin.How many moles of aspirin is this?

A)1.80 × 10^-6 mol
B)1.80 × 10^-3 mol
C)0.554 mol
D)554 mol
E)1.96 × 10²³ mol

Question 45

When solutions of sodium sulfide and copper(II)sulfate are mixed,a precipitate of copper(II)sulfide is formed.What is the net ionic equation for this reaction?

A)Na₂S(aq)+ CuSO₄(aq)→ Na₂SO₄(aq)+ CuS(s)
B)Na₂S(aq)+ CuSO₄(aq)→ CuS(s)
C)Cu²⁺(aq)+ S^2-(aq)→ Cu(s)+ S(s)
D)Cu²⁺(aq)+ S^2-(aq)→ CuS(s)
E)2Na⁺(aq)+ S^2-(aq)+ Cu²⁺(aq)+ SO₄^2-(aq)→ 2Na⁺(aq)+ SO₄^2-(aq)

Question 46

How many moles of hydrogen gas are needed to react with oxygen to form one mole of water? 2H₂(g)+ O₂(g)→ 2H₂O(l)

A)0.5 mol
B)1 mol
C)2 mol
D)4 mol
E)6 mol

Question 47

Choose the best classification of the reaction represented by the following equation: Na₂SO₄(aq)+ Ba(OH)₂(aq)→ BaSO₄(s)+ 2NaOH(aq)

A)decomposition
B)combination
C)single-replacement
D)double-replacement
E)None of the choices are correct.

Question 48

Choose the best classification of the reaction represented by the following equation: 2KClO₃(s)→ 2KCl(s)+ 3O₂(g)

A)decomposition
B)combination
C)single-replacement
D)double-replacement
E)None of the choices are correct.

Question 49

How many aspirin molecules are present in a 0.325 g sample of aspirin? [Molar mass: aspirin,180.2 g/mol]

A)1.09 × 10²¹ molecules
B)1.80 × 10⁻³ molecules
C)1.96 × 10²³ molecules
D)3.91 × 10²³ molecules
E)58.57 molecules

Question 50

How many iron atoms are present in 0.552 mol of iron?

A)2.798 × 10²⁴
B)6.02 × 10²³
C)27.98
D)3.32 × 10²³
E)55.85

Question 51

Consider the following precipitation reaction.Which of the following correctly identifies the spectator ions in this reaction? Na₂S(aq)+ CuSO₄(aq)→ Na₂SO₄(aq)+ CuS(s)

A)Na²⁺,S^2-,Cu²⁺,and SO₄2-
B)Na⁺,S^2-,Cu²⁺,and SO₄2-
C)Na⁺ and SO₄2-
D)Cu²⁺ and S^2-
E)There are no spectator ions present.

Question 52

Consider the hypothetical reaction: 3A₂ + 2B → C + 2D If 6.0 moles of A are mixed with 2.0 moles of B,what is the maximum amount of C that can be formed?

A)1.0 mol
B)2.0 mol
C)5.0 mol
D)6.0 mol
E)8.0 mol

Question 53

Incomplete combustion occurs when there is insufficient oxygen to react with a compound.The suffocating gas carbon monoxide is a product of incomplete combustion.How many moles of oxygen gas are required for the complete combustion of 11.0 moles of C₆H₁₄,a component of gasoline? C₆H₁₄(l)+ 19O₂(g)→ 12CO₂(g)+ 14H₂O(l)

A)1.16 mol O₂
B)28.0 mol O₂
C)105 mol O₂
D)209 mol O₂
E)418 mol O₂

Question 54

Classify the following reaction: Ce⁴⁺(aq)+ Fe²⁺(aq)→ Ce³⁺(aq)+ Fe³⁺(aq)

A)precipitation
B)acid - base
C)oxidation - reduction
D)decomposition
E)neutralization

Question 55

Methanol (CH₃OH)is the fuel used by racecars in the Indianapolis 500.It burns in the engine according to the equation below.How many moles of oxygen gas are necessary to react completely with 12.5 L of methanol? [Density: CH₃OH,0.7910g/mL; Molar mass: CH₃OH,32.05 g/mol] 2CH₃OH(l)+ 3O₂(g)→ 2CO₂(g)+ 4H₂O(g)

A)0.462 mol
B)2.16 mol
C)463 mol
D)740 mol
E)1850 mol

Question 56

Methanol (CH₃OH)is the fuel used by racecars in the Indianapolis 500.It burns in the engine according to the equation below.How many moles of oxygen gas are necessary to react completely with 425 moles of methanol? 2CH₃OH(l)+ 3O₂(g)→ 2CO₂(g)+ 4H₂O(g)

A)3 mol
B)255 mol
C)283 mol
D)638 mol
E)1275 mol

Question 57

What is the mass of a 0.0200 mol sample of nicotine? [Formula mass: nicotine,162.2 amu]

A)1.23 × 10^-4 g
B)0.308 g
C)3.24 g
D)32.4 g
E)8.11 × 10³ g

Question 58

Prozac,a drug prescribed to treat depression,has the formula C₁₇H₁₈F₃NO.If a patient was administered 15.0 mg of Prozac,how many moles of Prozac did he receive? [Molar mass: Prozac,309.36 g/mol]

A)4.85 × 10⁻⁵ mol
B)48.5 mol
C)20.6 mol
D)4640 mol
E)2.92 × 10¹⁹ mol

Question 59

How many molecules are present in a 0.0200 mol sample of nicotine?

A)0.0400 molecules
B)1.20 × 10²² molecules
C)2.41 × 10²² molecules
D)6.02 × 10²³ molecules
E)1.20 × 10²³ molecules

Question 60

Which of the choices is the correctly balanced form of the following equation? C₆H₁₄(l)+ O₂(g)→ CO₂(g)+ H₂O(l)

A)C₆H₁₄(l)+ 13O₂(g)→ 6CO₂(g)+ 7H₂O(l)
B)C₆H₁₄(l)+ 19O(g)→ 6CO₂(g)+ 7H₂O(l)
C)C₆H₁₄(l)+ 19O₂(g)→ 6CO₂(g)+ 7H₂O(l)
D)2C₆H₁₄(l)+ 19O₂(g)→ 12CO₂(g)+ 14H₂O(l)
E)C₁₂H₂₈(l)+ 38O(g)→ 12CO₂(g)+ 14H₂O(l)

Question 61

Choose the best classification of the reaction represented by the following equation: 2Fe³⁺(aq)+ Fe(s)→ 3Fe²⁺(aq)

A)neutralization
B)decomposition
C)acid-base
D)oxidation-reduction
E)precipitation

Question 62

The formula mass of a compound is calculated by adding together the number of atoms that make up the compound.

Question 63

Choose the best classification of the reaction represented by the following equation: BaCl₂(aq)+ K₂SO₄(aq)→ BaSO₄(s)+ 2KCl(aq)

A)single-replacement
B)double-replacement
C)combination
D)decomposition
E)oxidation-reduction

Question 64

The formula mass of water is 18.02 g.

Question 65

Select the ionic compound that is insoluble in water.

A)Na₂CO₃
B)Fe(NO₃)₃
C)KBr
D)MgS
E)NH₄Br

Question 66

In an acid-base reaction,what is transferred from the acid to the base?

A)an electron
B)a hydrogen cation,H⁺
C)a chloride anion,Cl^-
D)a sodium cation,Na⁺
E)a hydroxide anion,OH^-

Question 67

What is the mass of 4.35 moles of aluminum?

A)0.163 g
B)117 g
C)2.62 × 10²⁴ g
D)9.78 × 10²² g
E)27.8 g

Question 68

What is the mass of 3.5 × 10²² molecules of CO₂?

A)5.9 × 10^-2 g
B)2.6 g
C)1.8 × 10²⁴ g
D)1.5 × 10^-3 g
E)3.9 g

Question 69

Calculate the number of moles of BaF₂ in a 10.0 g sample of BaF₂.

A)9.77 mol
B)0.115 mol
C)17.4 mol
D)0.0631 mol
E)0.0570 mol

Question 70

Choose the best classification of the reaction represented by the following equation: HBr(aq)+ KOH(aq)→ KBr(aq)+ H₂O(l)

A)oxidation-reduction
B)combination
C)precipitation
D)decomposition
E)acid-base

Question 71

The term "molecular mass" is appropriately used for covalent compounds,but not ionic compounds.

Question 72

If the atomic mass of hydrogen is 1.01 amu,a mole of H₂ will weigh 1.01 g.

Question 73

The conversion of Fe²⁺ to Fe³⁺ is an oxidation reaction.

Question 74

One atomic mass unit is the same as one gram.

Question 75

One gram of gold (atomic mass 197 amu)contains more atoms than one gram of copper (atomic mass 63.55 amu).

Question 76

Choose the best classification of the reaction represented by the following equation: Pb(NO₃)₂(aq)+ CaCl₂(aq)→ PbCl₂(s)+ Ca(NO₃)₂(aq)

A)neutralization
B)acid-base
C)decomposition
D)precipitation
E)oxidation-reduction

Question 77

Consider the hypothetical reaction: 3A₂ + 2B → C + 2D When 25 g of reactant A and 34 g of reactant B are combined,the theoretical yield of product C is 31 g.If the actual yield of product C is 19 g,what is the percent yield of C?

A)53%
B)61%
C)76%
D)56%
E)85%

Question 78

One mole of iron contains 6.022 × 10²³ grams of Fe.

Question 79

What is the precipitate that forms when solutions of Na₃PO₄ and Fe(NO₂)₃ are mixed?

A)NaNO₃
B)NaFe
C)FePO₄
D)PO₄NO₃
E)Fe₃PO₄

Question 80

Choose the best classification of the reaction represented by the following equation: MgO(s)+ CO₂(g)→ MgCO₃(s)

A)single-replacement
B)double-replacement
C)combination
D)decomposition
E)precipitation