$$1.0 \times 10$$^{-9}$$\ \mathrm{M}$$

$$6.3 \times 10$$^{-12}$$\ \mathrm{M}$$

Question 1

Which of the following best describes a Brønsted-Lowry acid?

Accepted Answer

A substance that donates a proton (H+) to another substance.

Question 2

Given the reaction: $$\mathrm{HCl} + \mathrm{H_2O} \rightarrow \mathrm{H_3O^+} + \mathrm{Cl^-}$$, which species is the conjugate base?

Accepted Answer

$$\mathrm{Cl^-}$$

Question 3

A solution has $$[\mathrm{H^+}] = 2.5 	imes 10$$^{-4}$$\ \mathrm{M}. $$What is its pH?

Accepted Answer

$$2.60$$

Question 4

Which of the following is NOT a strong acid?

Accepted Answer

$$\mathrm{HC_2H_3O_2}$$

Question 5

What is the $$[\mathrm{OH^-}] in a $$solution with $$[\mathrm{H^+}] = 1.0 	imes 10$$^{-5}$$\ \mathrm{M} at$$ $$25^\circ\mathrm{C}$$?

Accepted Answer

$$1.0 	imes 10$$^{-9}$$\ \mathrm{M}$$

Question 6

Which of the following solutions is most basic according to the pH scale?

Accepted Answer

1 M NaOH (pH = 14.0)

Question 7

A 0.10 M solution of $$\mathrm{NaOH} is $$prepared. What is the pH of the solution?

Accepted Answer

$$13.00$$

Question 8

Which of the following best describes the autoionization of water?

Accepted Answer

Water molecules transfer protons to each other, producing $$\mathrm{H^+}$$ and $$\mathrm{OH^-}$$ ions.

Question 9

Calculate the pOH of a solution with $$[\mathrm{OH^-}] = 3.2 	imes 10$$^{-4}$$\ \mathrm{M}.$$

Accepted Answer

$$3.49$$

Question 10

Which of the following is a polyprotic acid?

Accepted Answer

$$\mathrm{H_2SO_4}$$

Question 11

A solution of $$\mathrm{NH_3$} in $$water has a pH of 11.2. What is the $$[\mathrm{H^+}]$$?

Accepted Answer

$$6.3 	imes 10$$^{-12}$$\ \mathrm{M}$$

Question 12

Which of the following is the correct equilibrium expression for the dissociation of acetic acid ($$\mathrm{HC_2H_3O_2}$$)?

Accepted Answer

$$K_a = \frac{[H^+][C_2H_3O_2^-]}{[HC_2H_3O_2]}$$

Question 13

If the $$K_w$$ for water at $$25^\circ\mathrm{C} is$$ $$1.0 	imes 10$$^{-14}$$, what is the pH of pure water?

Accepted Answer

$$7.00$$

Question 14

Which of the following is a conjugate acid-base pair?

Accepted Answer

$$\mathrm{NH_3$}$$ / $$\mathrm{NH_4$^+}$$

Question 15

A solution has a pOH of 3.0. What is its pH?

Accepted Answer

$$11.0$$

Question 16

Which of the following best explains why $$\mathrm{H_2SO_4} is $$considered a strong acid?

Accepted Answer

It completely donates its first proton in water.

Question 17

Calculate the pH of a $$0.020\ \mathrm{M}$$ solution of $$\mathrm{$$HNO_3$$}.$$

Accepted Answer

$$1.70$$

Question 18

Which of the following is true for a weak base in water?

Accepted Answer

It partially accepts protons from water, establishing an equilibrium.

Question 19

A $$0.15\ \mathrm{M}$$ solution of $$\mathrm{$$HIO_3$$}$$ has $$K_a = 0.17. $$What is the pH? (Use the quadratic formula if necessary.)

Accepted Answer

$$1.01$$

Question 20

Which of the following best describes the relationship between pH and pOH in aqueous solution at $$25^\circ\mathrm{C}$$?

Accepted Answer

$$\mathrm{pH} + \mathrm{pOH} = 14.00$$

Acid-Base Equilibria: Definitions, Calculations, and Examples

Study Guide - Practice Questions