Chemical Reaction Exam

Which product in the following chemical reaction is dissolved in solution?

CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)

A        HCl

B        CaCl2

C        CO2

D        H2O

1. B

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1. Which unbalanced formula equation best represents the following word equation?
2. iron(III) oxide + carbon monoxide → iron + carbon dioxide

A        Fe2O3 + CO → Fe + CO2

B        FeO + CO → Fe + CO2

C        Fe2O3 + CO2 → Fe + CO

D        FeO + CO2 → Fe + CO

1. A

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Which of the following equations is balanced?

A        C2H6 + O2 → CO2 + H2O

B        C2H6 + O2 → 2CO2 + 3H2O

C        C2H6 + 7O2 → 2CO2 + 3H2O

D        2C2H6 + 7O2 → 4CO2 + 6H2O

1. D

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Which of the following chemical reactions is a combination reaction?

A        2H2O(l) → 2H2(g) + O2(g)

B        2H2(g) + O2(g) → 2H2O(l)

C        H2O2 → H2 + O2(g)

D        H2O + Na → NaOH + H2

1. B

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Which is the best term to describe the following reaction?

CaCO3(s) → CaO(s) + CO2(g)

1. combination reaction
2. metal displacement reaction
3. precipitation reaction
4. decomposition reaction

1. D

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When solutions of sodium chloride (NaCl) and silver nitrate (AgNO3) are mixed, solid silver chloride (AgCl) forms. Which ions remain dissolved in the solution?

A        Na+ and Cl−

B        Ag+ and Cl−

C        Na+ and [pic 1]

D        Ag+ and [pic 2]

1. C

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Define the process of reduction.

A        Reduction is the loss of oxygen or the gain of electrons.

B        Reduction is the gain of oxygen or the loss of electrons.

C        Reduction is the gain of oxygen or electrons.

D        Reduction is the loss of oxygen or electrons.

1. A

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What is the main reason limestone is added to a blast furnace?

A        to produce the carbon monoxide that reduces the iron or to iron metal

B        to react with the carbon in the coke to produce carbon dioxide

C        to reduce the iron ore to iron metal

D        to react with the silicates in the ore and produce the slag that can be separated from the molten iron

1. D

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Explain why crushing solid reactants helps to increase the rate of reaction.

A        It exposes more of the solid reactant to the other reactants so there can be more reactions occurring at any one time.

B        It weakens the chemical bonds in the solid so that it is easier for the reaction to occur.

C        It helps the solid to dissolve.

D        All answers are correct.

1. A

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Explain why adding a catalyst to a reaction increases the rate of reaction.

A        The catalyst can provide a pathway for the chemical reaction that requires less energy.

B        The catalyst can help the reactant molecules to come together and react.

C        The catalyst can force reactants into the correct arrangement so that they react.

D        All answers are correct.

1. D

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