Deck 9: Chemical Change

Question 1

What happens when a strong acid is placed in water?

A)The solution cools as the hydronium ions form
B)Hydrogen gas is released by the reaction of the acid with the water
C)The acid remains in its molecular form
D)The water separates completely into ions
E)The acid dissociates completely into ions

Answer 1

The acid dissociates completely into ions

Question 2

Which of the following gives the correct formulas and ratio of ions present when sodium carbonate is dissolved in water?

A)S^2-(aq) + CO²⁺(aq)
B)2 Na⁺(aq) + CO₃^2-(aq)
C)2 Na⁺(aq) + C⁴⁺(aq) + 3 O^2-(aq)
D)Na²⁺(aq) + CO₄^2-(aq)
E)2 Na⁺(aq) + CO₄^2-(aq)

Answer 2

2 Na⁺(aq) + CO₃^2-(aq)

Question 3

Which of the following is the best explanation of why a weak acid is a poor conductor?

A)The weak acid molecules undergo a precipitation reaction in aqueous solution
B)The weak acid molecules move too slowly to conduct well
C)It is only slightly ionized in water
D)It can form only dilute solutions in water
E)It will not dissolve in water

Answer 3

It is only slightly ionized in water

Question 4

Some solutes have solutions that conduct electricity,but poorly.Which of the following terms best describes these solutes?

A)Highly charged ions
B)Ions with fractional charges
C)Nonconductor
D)Weak electrolyte
E)Cation solutions

Question 5

A solute whose solution is a good conductor of electricity is classified into which of the following categories?

A)a molecular substance
B)a weak electrolyte
C)a strong electrolyte
D)a nonelectrolyte
E)an insulator

Question 6

Which of the following is the best description of a total ionic equation?

A)An equation that expresses soluble ionic compounds with their standard formulas,e.g.,sodium chloride as NaCl(aq).
B)An equation that expresses strong acids with their standard formulas,e.g.,hydrochloric acid as HCl(aq).
C)An equation that expresses both soluble ionic compounds and strong acids with their standard formulas.
D)An equation that expresses both soluble ionic compounds and strong acids as ions,e.g.,sodium chloride as Na⁺(aq)+ Cl⁻(aq)and hydrochloric acid as H⁺(aq)+ Cl⁻(aq).
E)An equation that has no spectator ions,indicating exactly what chemical change takes place and nothing else.

Question 7

What ions are present in what ratio in a solution of aqueous calcium chloride?

A)Ca²⁺(aq) + Cl₂^2-(aq)
B)Ca²⁺(aq) + Cl₂^-(aq)
C)Ca²⁺(aq) + 2 Cl^-(aq)
D)CaCl⁺(aq) + Cl^-(aq)
E)Ca²⁺(aq) + Cl^2-(aq)

Question 8

What are the formulas of the major species present in a mixture of HNO₃ and HF in water?

A)HNO₃(aq) + HF(aq)
B)HNO₃(aq) + H⁺(aq) + F^-(aq)
C)H⁺(aq) + NO₃(aq) + F^-(aq)
D)H⁺(aq) + NO₃^-(aq) + HF(aq)
E)H₂(g) + NO₃^-(aq) + F⁺(aq)

Question 9

What ions are present in what ratio in an aqueous solution of iron(III)sulfate?

A)Fe₂²⁺(aq) + SO₄^2-(aq)
B)Fe₂²⁺(aq) + SO₃^2-(aq)
C)2 Fe³⁺(aq) + 12 SO^2-(aq)
D)2 Fe³⁺(aq) + 3 SO₄^2-(aq)
E)Fe³⁺(aq) + S^2-(aq) + O^2-(aq)

Question 10

Which of the following statements is incorrect?

A)It is the movement of ions that makes up an electric current in a solution
B)A sugar solution is a nonconductor because no ions are present
C)An electric current is a movement of electric charge
D)There are no free-to-move electrons in a solution
E)Cations in a solution move toward the positively charged electrode

Question 11

Which of the following is a weak acid?

A)Hydrochloric acid, HCl
B)Hydrocyanic acid, HCN
C)Chloric acid, HClO₃
D)Nitric acid, HNO₃
E)Sulfuric acid, H₂SO₄

Question 12

In which pair are both strong acids?

A)HF and HCl
B)HC₂H₃O₂ and HN₃
C)HNO₂ and H₂SO₃
D)H₂CO₃ and H₃PO₄
E)HClO₄ and HI

Question 13

Consider a solution in which the solute exists only as the molecules shown below. Which of the following describes this solute?

A)nonelectrolyte
B)strong electrolyte
C)weak electrolyte
D)ionic

Question 14

What ions are present in what ratio in a solution of aqueous (NH₄)₂SO₄?

A)(NH₄)₂²⁺(aq) + SO₄^2-(aq)
B)2 NH₄⁺(aq) + SO₄^2-(aq)
C)NH₄⁺(aq) + SO₄^-(aq)
D)2 N^3-(aq) + 8 H⁺(aq) + 4 SO^2-(aq)
E)2 N^3-(aq) + 8 H⁺(aq) +S^2-(aq) + 4 O^2-(aq)

Question 15

Which of the following correctly describes an electric current?
i.Spontaneous flow of protons in gold,silver,copper,or aluminum wires
ii.Exchange of protons between cations in a solution
iii.The movement of ions in a solution
iv.The movement of negatively charged electrons in a metal

A)i only
B)iv only
C)i and ii
D)iii and iv
E)i, ii, and iv

Question 16

Which of the following is the best description of what happens when a weak acid is placed in water?

A)The acid is only slightly dissociated
B)About half of the water molecules dissociate into ions
C)The acid almost completely ionizes
D)A chemical reaction results in the production of hydrogen gas
E)A large amount of electrical current is generated, although it is weak

Question 17

If a solution conducts electricity,it is positive evidence that...

A)molecules are dissolved in the solution.
B)the solution is pure water.
C)the solute must be a nonelectrolyte.
D)the solute is an strong electrolyte.
E)mobile ions are present.

Question 18

What ions are present in an aqueous solution of hydrochloric acid?

A)H₂⁺(aq) + Cl₂^-(aq)
B)HCl(aq)
C)H⁺(aq) + Cl^-(aq)
D)H₃O⁺(aq) + ClO₃^-(aq)
E)H⁺(aq) + ClO₃^-(aq)

Question 19

How should pure water be classified with respect to its electrical conductivity properties?

A)Weak electrolyte
B)Nonelectrolyte
C)Strong electrolyte
D)Good conductor
E)Weak conductor

Question 20

Which of the following is the best explanation of why a strong acid is an excellent conductor?

A)It is almost completely ionized in water
B)It undergoes a vigorous chemical reaction with the water molecules
C)It is immiscible in water
D)All acids are natural conductors
E)It reduces electronic vibration and thus allows greater conductivity

Question 21

Write the equation for the complete oxidation of HC₂H₃O₂.What is the sum of the coefficients?

A)4 or less
B)5
C)6
D)7
E)8 or more

Question 22

Write the net ionic equation for the reaction that occurs,if any,when solutions of aluminum nitrate and sodium hydroxide are combined,producing an insoluble precipitate.What is/are the products?

A)NaNO₃(s) + Al(OH)₃(s)
B)NaNO₃(s)
C)3 Na⁺(aq) + 3 NO₃^-(s) + Al(OH)₃(s)
D)Al(OH)₃(s)
E)There is no reaction

Question 23

Which of the following substances will precipitate from an aqueous solution?

A)NaF
B)CaCO₃
C)NH₄Cl
D)K₂SO₄
E)Cu(NO₃)₂

Question 24

Write the net ionic equation for the reaction that occurs,if any,when solutions of silver chlorate and sodium sulfide are combined.What are the reactants (with appropriate coefficients)?

A)Na⁺(aq) + Cl^-(aq)
B)Na⁺(aq) + ClO₃^-(aq)
C)Ag²⁺(aq) + S^2-(aq)
D)2 Ag⁺(aq) + SO₄^2-(aq)
E)2 Ag⁺(aq) + S^2-(aq)

Question 25

Ethane,C₂H₆ ,is a component of natural gas and is used in home gas ranges. In the balanced equation for this reaction what is the coefficient of water?

A)4 or less
B)5
C)6
D)7
E)8 or more

Question 26

Write the net ionic equation for the reaction that occurs,if any,when cesium metal (Z = 55)is placed in hydrochloric acid.Cesium metal is above hydrogen gas in the activity series.

A)Cs(s) + H⁺(aq) → H(g) + Cs⁺(aq)
B)2 Cs(s) + 2 H⁺(aq) → H₂(g) + 2 Cs⁺(aq)
C)2 Cs(s) + 2 H⁺(aq) + 2 Cl^-(aq) → H₂(g) + 2 Cs⁺(aq) + 2 Cl^-(aq)
D)2 Cs(s) + 2 HCl(aq) → H₂(g) + 2 CsCl(aq)
E)There is no reaction

Question 27

Write the equation for the complete oxidation of C₄H₈O.What is the coefficient for O₂?

A)2
B)4
C)8
D)11
E)12

Question 28

Ethanol,C₂H₅OH,is burned.Write the balanced chemical equation for this reaction.What is the coefficient for H₂O?

A)2
B)3
C)4
D)5
E)6

Question 29

Which of the following is the best description of a net ionic equation?

A)An equation that expresses soluble ionic compounds with their standard formulas,e.g.,sodium chloride as NaCl(aq).
B)An equation that expresses strong acids with their standard formulas,e.g.,hydrochloric acid as HCl(aq).
C)An equation that expresses both soluble ionic compounds and strong acids with their standard formulas.
D)An equation that expresses both soluble ionic compounds and strong acids as ions,e.g.,sodium chloride as Na⁺(aq)+ Cl⁻(aq)and hydrochloric acid as H⁺(aq)+ Cl⁻(aq).
E)An equation that has no spectator ions,indicating exactly what chemical change takes place and nothing else.

Question 30

What is the net ionic equation for the preparation of Ca₃(PO₄)₂(s)from aqueous solution?

A)3 Ca²⁺(aq) + 2 PO₄^3-(aq) → Ca₃(PO₄)₂(s)
B)3 Ca(s) + 2 PO₄(aq) → Ca₃(PO₄)₂(s)
C)3 CaO(aq) + 2 P₂(s) + 3 O₂(g) → Ca₃PO₄(aq) + 2 PO₄(g)
D)3 Ca²⁺(aq) + 2 PO₃^-(aq) + 2 O^2-(g) → Ca₃(PO₄)₂(aq)
E)3 Ca⁺(aq) + 2 PO₄^-(aq) → Ca₃(PO₄)₂(s)

Question 31

Propane,C₃H₈,is burned as a fuel in heating homes.Write the balanced chemical equation for this reaction.What is the coefficient for CO₂?

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

Question 32

In the net ionic equation for the following,what are the spectator ions? NH₄NO₃(aq)+ KCl(aq)→ KNO₃(aq)+ NH₄Cl(aq)

A)None of the ions are spectator ions
B)The cations are spectators; the anions are not
C)All the ions are spectators
D)The anions are spectators; the cations are not
E)The potassium ions are spectators

Question 33

Write the net ionic equation for the reaction that occurs,if any,when gold is placed in a solution of hydrobromic acid.Hydrogen gas is above gold in the activity series.What are the products?

A)H₂(g) + 2 AuBr(aq)
B)H₂(g) + 2 Au⁺(aq) + 2 Br^-(aq)
C)H₂(g) + 2 Au⁺(aq)
D)H₂(g) + Au²⁺(aq)
E)There is no reaction

Question 34

What are the reactants in the net ionic equation for the reaction that has magnesium phosphate as the only solid product?

A)3 Mg²⁺(aq) + 2 P^3-(aq)
B)Mg²⁺(aq) + PO₃^2-(aq)
C)Mg²⁺(aq) + PO₄^2-(aq)
D)3 Mg²⁺(aq) + 2 PO₃^3-(aq)
E)3 Mg²⁺(aq) + 2 PO₄^3-(aq)

Question 35

Write the net ionic equation for the reaction between copper and AgC₂H₃O₂.The apparatus for the reaction is shown below. Regard all salts containing acetate ion as soluble in water.Copper is above silver in the activity series.What will appear on the product side of the balanced net ionic equation?

A)Cu(s) + 2 Ag⁺(aq)
B)Cu²⁺(aq) + 2 Ag(s)
C)C₂H₃O₂^-(aq) + Ag⁺(aq)
D)Cu(aq) + 2 Ag⁺(s)
E)2 Cu(s) + AgC₂H₃O₂(aq)

Question 36

What is the net ionic equation for the single replacement reaction Ca(s)+ 2 HNO₃(aq)→ H₂(g)+ Ca(NO₃)₂(aq)Calcium is above hydrogen in the activity series.

A)Ca(s) + NO₃^-(aq) → CaNO₃^-(aq)
B)2 H⁺(aq) → H₂(g)
C)Ca(s) + 2 H⁺(aq) + 2 NO₃^-(aq) → Ca²⁺(aq) + H₂(g) + N₂O(g)
D)Ca(s) + 2 H⁺(aq) → Ca²⁺(aq) + H₂(g)
E)Ca(s) + 2 H⁺(aq) + 2 NO₃^-(aq) → H₂(g) + Ca²⁺(aq) + 2 NO₃^-(aq)

Question 37

What is the net ionic equation corresponding to the formation of Cu(OH)₂(s)from aqueous solution?

A)C²⁺(aq) + U²⁺(aq) + 2 OH^2-(aq)→ Cu(OH)₂(s)
B)Cu(s) + O₂(g) + H₂(g) → Cu(OH)₂(s)
C)Cu⁺(aq) + 2 OH^-_(l)→ Cu(OH)₂(s)
D)Cu²⁺(aq) + (OH)₂^2-(aq) → Cu(OH)₂(s)
E)Cu²⁺(aq) + 2 OH^-(aq) → Cu(OH)₂(s)

Question 38

What are the spectator ions in the reaction between HCl and AgNO₃ in dilute aqueous solution? The reaction is shown below. Given that AgCl is insoluble in water and that AgNO₃ is soluble,

A)Ag⁺(aq) + Cl^-(aq)
B)Cl^-(aq) + NO₃^-(aq)
C)NO₃^-(aq) + H⁺(aq)
D)Ag⁺(aq) + H⁺(aq)
E)There are no spectator ions in this reaction

Question 39

Write the net ionic equation for the reaction that occurs,if any,when a calcium chip is dropped into a hydrochloric acid solution.Calcium is above hydrogen in the activity series.What are the reactants (with appropriate coefficients)?

A)Ca(s) + 2 HCl(aq)
B)Ca(s) + 2 H⁺(aq)
C)Ca²⁺(aq) + 2 H⁺(aq)
D)Ca(s) + H₂⁺(aq)
E)There is no net reaction

Question 40

Write the equation for the complete oxidation of C₃H₇COC₂H₅.What is the sum of the coefficients?

A)45
B)43
C)31
D)30
E)none of the above

Question 41

Which of the following combinations of reactant does not produce a net change as shown by a net ionic equation?

A)K₂CO₃(aq) + CaCl₂(aq)
B)HCl(aq) + NaOH(aq)
C)NaNO₃(aq) + NH₄Cl(aq)
D)Na₂CO₃(aq) + H₂SO₄(aq)
E)Li₂SO₃(aq) + HCl(aq)

Question 42

What appears on the right side of the equation in the net ionic equation for the reaction between Ca(C₂H₃O₂)₂ and HCl,where all salts are soluble in water?

A)H⁺(aq) + C₂H₃O₂^-(aq)
B)No reaction
C)HC₂H₃O₂(aq)
D)Ca²⁺(aq) + 2 Cl^-(aq)
E)Ca(C₂H₃O₂)₂(aq) + HCl(aq)

Question 43

Write the net ionic equation for the reaction that produces solid silver sulfide.What are the reactants?

A)2 Ag⁺(aq) + S^2-(aq)
B)Ag⁺(aq) + S^-(aq)
C)Ag²⁺(aq) + 2 S^-(aq)
D)Ag²⁺(aq) + S^2-(aq)
E)2 Ag⁺(aq) + SO₄^2-(aq)

Question 44

What is the preferred way to write H₂CO₃ when it appears as a product in a net ionic equation?

A)H₂(g) + C(s) + 1.5 O₂(g)
B)H₂(g) + CO₃(aq)
C)H₂O₂(aq) + CO(g)
D)HCO₃^-(aq) + H⁺(aq)
E)H₂O_(l) + CO₂(g)

Question 45

In the balanced net ionic equation for the reaction of solid CaCO₃ and aqueous hydrochloric acid,which produces aqueous chloride and an acid that decomposes into the other two products,what appears on the left side of the net ionic equation?

A)CaCO₃(s) + 2 H⁺(aq) + 2 Cl^-(aq)
B)CaCO₃(s) + 2 Cl^-(aq)
C)CaCO₃(aq) + HCl(aq)
D)CaCO₃(s) + 2 H⁺(aq)
E)Ca²⁺(aq) + 2 Cl^-(aq)

Question 46

When it appears on the right side of a net ionic equation,ammonium hydroxide must be rewritten in another form.How should "ammonium hydroxide" appear on the net ionic equation as a product?

A)NH₄⁺(aq) + OH^-(aq)
B)NH₃(aq) + H₂O_(l)
C)NH₃(aq) + OH^-(g)
D)NH₃(g) + H₂O(aq)
E)NH₃OH_(l) + H⁺(aq)

Question 47

Which of the following could be a product that would appear in the net ionic equation for a reaction that yields a molecular product?

A)H⁺(aq)
B)AgCl(s)
C)Br^-(aq)
D)H₂O_(l)
E)Any of the seven common strong acids

Question 48

In the net ionic equation for the reaction between a weak acid and strong base,what are the major species on the reactants side?

A)Molecules of acid; ions of the base
B)Molecules of acid; molecules of base
C)Ions of the acid; ions of the base
D)Ions of the acid; molecules of base
E)All species are spectator ions, thus there are no major species on the reactants side

Question 49

Which of the following is a product of a reaction that will always be included in the net ionic equation for the reaction?

A)NH₃
B)CO₂
C)SO₃
D)H₂O
E)all of the above

Question 50

Write the net ionic equation for the reaction that produces solid aluminum phosphate.What are the reactants?

A)Al³⁺(aq) + PO₄^3-(aq)
B)Al³⁺(aq) + P^3-(aq)
C)Al(s) + PO₄(s)
D)Al(aq) + PO₄(aq)
E)Al³⁺(aq) + HPO₄^2-(aq)

Question 51

What appears on the product side in the net ionic equation for the reaction of HNO₃(aq)with KOH(aq).KNO₃ is water soluble.

A)NO₃^-(aq) + K⁺(aq)
B)H₂O_(l)
C)H⁺(aq) + K⁺(aq)
D)H₂(g) + O₂(g)
E)K⁺(aq) + NO₃^-(aq)

Question 52

What is the net ionic equation for the reaction of any strong acid with a soluble,strong hydroxide base,such as NaOH?

A)H⁺(aq) + Na⁺(aq) → H₂O_(l) + Na(s)
B)H₂(g) + 2 OH^-(aq) → 2 H₂O_(l)
C)2 H⁺(aq) + O(g) → H₂O(aq)
D)H⁺(aq) + OH^-(aq) → H₂O_(l)
E)3 H⁺(aq) + OH^-(aq) → H₂(g) + H₂O_(l)