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 two aqueous solutions combine to form an insoluble solid.

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 will NOT conduct electricity when dissolved in water?

Accepted Answer

Silver chloride ($$\mathrm{AgCl})$$

Question 5

A student mixes solutions of sodium carbonate ($$\mathrm{Na_2CO_3}) $$and copper(II) chloride ($$\mathrm{$$CuCl_2$$}). $$Which product will precipitate?

Accepted Answer

$$\mathrm{$$CuCO_3$$}$$

Question 6

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

Accepted Answer

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

Question 7

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

Accepted Answer

You must balance free elements last by adjusting their coefficients.

Question 8

Which of the following is the correct classification for the reaction: $$\mathrm{2Na(s) + Cl_2$(g) \rightarrow 2NaCl(s)}$$?

Accepted Answer

Synthesis (combination) reaction

Question 9

A solution of potassium iodide ($$\mathrm{KI}) is $$mixed with a solution of lead(II) nitrate ($$\mathrm{Pb(NO_3$)_2}). $$What is the balanced equation for the reaction, including states?

Accepted Answer

$$2\mathrm{KI}(aq) + \mathrm{Pb(NO_3$)_2}(aq) \rightarrow 2\mathrm{$$KNO_3$$}(aq) + \mathrm{$$PbI_2$$}(s)$$

Question 10

Which of the following best describes a strong electrolyte?

Accepted Answer

A compound that completely dissociates into ions in water.

Question 11

Which of the following is a double-displacement reaction?

Accepted Answer

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

Question 12

Which of the following is the correct net ionic equation for the precipitation reaction between $$\mathrm{$$AgNO_3$$(aq)}$$ and $$\mathrm{NaCl(aq)}$$?

Accepted Answer

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

Question 13

Which of the following is NOT a redox reaction?

Accepted Answer

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

Question 14

Which of the following best describes the process that occurs when sodium chloride dissolves in water?

Accepted Answer

Sodium and chloride ions dissociate and move freely in solution.

Question 15

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

Accepted Answer

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

Question 16

Which of the following is a synthesis reaction?

Accepted Answer

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

Chapter 7: Chemical Reactions – Study Notes for Introductory Chemistry

Study Guide - Practice Questions

Study Guide - Flashcards