Question 1

Which of the following observations is NOT considered evidence of a chemical reaction?

Accepted Answer

Water boils and bubbles form.

Question 2

Which of the following best describes a precipitation reaction?

Accepted Answer

A reaction in which a solid forms when two aqueous solutions are mixed.

Question 3

What is the balanced chemical equation for the combustion of methane ($$\mathrm{CH_4$}) in $$oxygen?

Accepted Answer

$$\mathrm{CH_4$} + 2\mathrm{O_2$} \rightarrow \mathrm{CO_2$} + 2\mathrm{H_2O}$$

Question 4

Which of the following compounds is insoluble in water?

Accepted Answer

$$\mathrm{AgCl}$$

Question 5

When solutions of potassium iodide ($$\mathrm{KI}) $$and lead(II) nitrate ($$\mathrm{Pb(NO_3$)_2}) $$are mixed, what is the precipitate formed?

Accepted Answer

$$\mathrm{$$PbI_2$$}$$

Question 6

Which of the following is a strong electrolyte when dissolved in water?

Accepted Answer

$$\mathrm{NaCl}$$

Question 7

Which of the following is the correct net ionic equation for the reaction between aqueous solutions of silver nitrate and sodium chloride?

Accepted Answer

$$\mathrm{Ag^+ (aq) + Cl^- (aq) \rightarrow AgCl (s)}$$

Question 8

Which of the following reactions is an example of an acid–base (neutralization) reaction?

Accepted Answer

$$\mathrm{HCl (aq) + NaOH (aq) \rightarrow NaCl (aq) + H_2O (l)}$$

Question 9

Which of the following best describes a redox (oxidation–reduction) reaction?

Accepted Answer

A reaction in which electrons are transferred between substances.

Question 10

Which of the following is the correct balanced equation for the decomposition of water by electrolysis?

Accepted Answer

$$2\mathrm{H_2O (l)} \rightarrow 2\mathrm{H_2$ (g)} + \mathrm{O_2$ (g)}$$

Question 11

Which of the following is a synthesis (combination) reaction?

Accepted Answer

$$\mathrm{2Na (s) + Cl_2$ (g) \rightarrow 2NaCl (s)}$$

Question 12

Which of the following is the correct molecular equation for the reaction between aqueous sodium carbonate and copper(II) chloride?

Accepted Answer

$$\mathrm{Na_2CO_3 (aq) + $$CuCl_2$$ (aq) \rightarrow 2NaCl (aq) + $$CuCO_3$$ (s)}$$

Question 13

Which of the following is a double-displacement reaction?

Accepted Answer

$$\mathrm{$$AgNO_3$$ (aq) + NaCl (aq) \rightarrow AgCl (s) + $$NaNO_3$$ (aq)}$$

Question 14

Which of the following statements about balancing chemical equations is correct?

Accepted Answer

You may only change the coefficients in front of chemical formulas to balance the equation.

Question 15

Which of the following is the correct net ionic equation for the reaction between hydrochloric acid and sodium hydroxide?

Accepted Answer

$$\mathrm{H^+ (aq) + OH^- (aq) \rightarrow H_2O (l)}$$

Question 16

Which of the following is a gas-evolution reaction?

Accepted Answer

$$\mathrm{Na_2CO_3 (aq) + 2HCl (aq) \rightarrow 2NaCl (aq) + H_2O (l) + CO_2$ (g)}$$

Question 17

Which of the following best describes why antacids relieve heartburn?

Accepted Answer

They react with stomach acid to form water and a salt, neutralizing excess acid.

Chapter 7: Chemical Reactions – Structured Study Notes

Study Guide - Practice Questions