Question 1

Which of the following best describes a molecular equation?

Accepted Answer

It shows the intact compound instead of their dissociated ionic forms.

Question 2

What is the correct balanced molecular equation for the reaction between $\mathrm{HCl}$ (aq) and $\mathrm{KOH}$ (aq)?

Accepted Answer

$\mathrm{HCl}~(aq) + \mathrm{KOH}~(aq) \rightarrow \mathrm{KCl}~(aq) + \mathrm{H_2O}~(l)$

Question 3

In a precipitation reaction, what must occur for a reaction to proceed?

Accepted Answer

At least one of the products must be insoluble in water.

Question 4

Which of the following is a correct example of a gas evolution reaction?

Accepted Answer

$\mathrm{H_2SO_4}~(aq) + \mathrm{Na_2CO_3}~(aq) \rightarrow \mathrm{Na_2SO_4}~(aq) + \mathrm{CO_2}~(g) + \mathrm{H_2O}~(l)$

Question 5

When $\mathrm{Ag_2SO_4}$ (aq) reacts with $\mathrm{KCl}$ (aq), which product is expected to precipitate?

Accepted Answer

$\mathrm{AgCl}$

Question 6

Which step is necessary when predicting the products of a double displacement reaction?

Accepted Answer

Swap the ionic partners and check the solubility of the products.

Question 7

Given $\mathrm{MgBr_2}$ (aq) and $\mathrm{Na_2C_2H_3O_2}$ (aq), what is the correct balanced molecular equation for their reaction?

Accepted Answer

$\mathrm{MgBr_2}~(aq) + 2\mathrm{NaC_2H_3O_2}~(aq) \rightarrow \mathrm{Mg(C_2H_3O_2)_2}~(aq) + 2\mathrm{NaBr}~(aq)$

Question 8

What is the net ionic equation for the reaction between $\mathrm{AgNO_3}$ (aq) and $\mathrm{NaCl}$ (aq)?

Accepted Answer

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

Question 9

Which of the following is a correct neutralization reaction?

Accepted Answer

$\mathrm{Ca(OH)_2}~(aq) + 2\mathrm{HCN}~(aq) \rightarrow \mathrm{Ca(CN)_2}~(aq) + 2\mathrm{H_2O}~(l)$

Question 10

If a reaction between two aqueous solutions produces only soluble products, what is the outcome?

Accepted Answer

No reaction occurs and we stop.

Question 11

Which of the following is NOT a type of chemical equation discussed in the study materials?

Accepted Answer

Combustion equation

Question 12

When balancing a molecular equation, what is the first step?

Accepted Answer

Break up the reactants into their ionic forms.

Question 13

Which of the following combinations will result in a precipitation reaction?

Accepted Answer

$\mathrm{ZnBr_2}~(aq) + 2\mathrm{KOH}~(aq) \rightarrow \mathrm{Zn(OH)_2}~(s) + 2\mathrm{KBr}~(aq)$

Question 14

In the reaction $\mathrm{LiOH}$ (aq) + $\mathrm{MgSO_4}$ (aq), what is the correct balanced molecular equation?

Accepted Answer

2$\mathrm{LiOH}~(aq) + \mathrm{MgSO_4}~(aq) \rightarrow \mathrm{Mg(OH)_2}~(s) + \mathrm{Li_2SO_4}~(aq)$

Question 15

Which of the following is a correct step when solving molecular equations?

Accepted Answer

Swap ionic partners by remembering that opposite charges attract.

Question 16

A student mixes $\mathrm{Ca(OH)_2}$ (aq) and $\mathrm{HCN}$ (aq). What type of reaction is this?

Accepted Answer

Neutralization reaction

Question 17

Which of the following is a correct example of a precipitation reaction?

Accepted Answer

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

Molecular Equations and Precipitation Reactions in GOB Chemistry

Study Guide - Practice Questions