Question 1

Which of the following statements best describes the role of a chemical catalyst in a reaction?

Accepted Answer

A catalyst lowers the activation energy, allowing the reaction to proceed faster.

Question 2

Given the following equilibrium: $$ \mathrm{N_2O_4(g) \rightleftharpoons 2NO_2(g)} $$, which of the following will increase the concentration of $$ \mathrm{NO_2$}  at $$equilibrium?

Accepted Answer

Adding more $$ \mathrm{N_2O_4}  to $$the system.

Question 3

A student dissolves $$ \mathrm{NaCl}  in $$water. Which statement best explains why $$ \mathrm{NaCl}  is $$classified as a strong electrolyte?

Accepted Answer

$$ \mathrm{NaCl} $$ completely dissociates into $$ \mathrm{Na^+} $$ and $$ \mathrm{Cl^-} $$ ions in water.

Question 4

Which of the following solutions will conduct electricity the best?

Accepted Answer

A solution of $$ \mathrm{NaCl}  in $$water.

Question 5

Which of the following compounds is a weak electrolyte in aqueous solution?

Accepted Answer

$$ \mathrm{CH_3COOH} $$

Question 6

A solution contains $$ 0.10 $$ mol of $$ \mathrm{Na_2SO_4} $$ dissolved in $$ 1.0  L of $$water. What is the total concentration of ions in the solution?

Accepted Answer

$$ 0.30 \ \mathrm{mol/L} $$

Question 7

Which of the following best describes the difference between a strong acid and a weak acid in water?

Accepted Answer

A strong acid completely ionizes in water, while a weak acid only partially ionizes.

Question 8

Which of the following is the correct net ionic equation for the reaction between $$ \mathrm{Na_2SO_4} $$ and $$ \mathrm{$$BaCl_2$$}  in $$aqueous solution?

Accepted Answer

$$ \mathrm{Ba$$^{2+}$$ (aq) + SO_4$^{2-} (aq) \rightarrow $$BaSO_4$$ (s)} $$

Question 9

A solution of $$ \mathrm{$$KNO_3$$}  is $$prepared by dissolving $$ 0.50 $$ mol in $$ 1.0  L of $$water. What is the concentration of $$ \mathrm{NO_3$^-} $$ ions in the solution?

Accepted Answer

$$ 0.50 \ \mathrm{mol/L} $$

Question 10

Which of the following best explains why $$ \mathrm{C_6H_{12}O_6$}  ($$glucose) is a nonelectrolyte?

Accepted Answer

It dissolves in water but does not produce ions.

Question 11

If $$ 0.20 $$ mol of $$ \mathrm{$$CaCl_2$$}  is $$dissolved in $$ 1.0  L of $$water, what is the concentration of $$ \mathrm{Cl^-} $$ ions?

Accepted Answer

$$ 0.40 \ \mathrm{mol/L} $$

Question 12

Which of the following is a characteristic of a weak electrolyte?

Accepted Answer

It partially dissociates into ions in solution.

Question 13

A patient is given an intravenous solution containing $$ \mathrm{NaCl} . $$Why is $$ \mathrm{NaCl} $$ chosen over $$ \mathrm{C_6H_{12}O_6$} $$ for this purpose?

Accepted Answer

$$ \mathrm{NaCl}  is a $$strong electrolyte and helps maintain the body's ionic balance.

Question 14

Which of the following pairs of compounds will form a precipitate when mixed in aqueous solution?

Accepted Answer

$$ \mathrm{$$BaCl_2$$} $$ and $$ \mathrm{Na_2SO_4} $$

Question 15

Which of the following is the correct ionic equation for the dissolution of $$ \mathrm{KBr}  in $$water?

Accepted Answer

$$ \mathrm{KBr (s) \rightarrow K^+ (aq) + Br^- (aq)} $$

Question 16

A solution of $$ \mathrm{CH_3COOH}  is $$tested for conductivity. What result is expected and why?

Accepted Answer

Low conductivity because it is a weak electrolyte.

Question 17

Which of the following statements is true regarding the solubility of $$ \mathrm{$$NaNO_3$$}  in $$water?

Accepted Answer

$$ \mathrm{$$NaNO_3$$}  is a $$strong electrolyte and highly soluble in water.

Question 18

A chemist mixes $$ \mathrm{$$BaCl_2$$} $$ and $$ \mathrm{Na_2SO_4}  in $$water. What is the driving force for the reaction?

Accepted Answer

Formation of a precipitate ($$ \mathrm{$$BaSO_4$$} ).$$

Study Notes: Atoms, Ions, and Isotopes

Guida di studio - Domande di pratica

Study guide - Flashcard