Chapter 10: Acids and Bases and Equilibrium

What is the molarity of a solution of HCL if 5ml of the HCL solution is titrated with 28.6ml of a 0.145 M NaOH solution?

$\mathrm{HCl}\left(aq\right)+\mathrm{NaOH}\left(aq\right)⟶{\mathrm{H}}_2\mathrm{O}\left(l\right)+\mathrm{NaCl}\left(aq\right)$

What is the molarity of an acetic acid solution if $25.0\mathrm{mL}$ of the ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$solution is titrated with $29.7\mathrm{mL}$of a $0.205\mathrm{M}$$\mathrm{KOH}$solution$?$

${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2\left(aq\right)+\mathrm{KOH}\left(aq\right)⟶{\mathrm{H}}_2\mathrm{O}\left(l\right)+{\mathrm{KC}}_2{\mathrm{H}}_3{\mathrm{O}}_2\left(aq\right)$

If $32.8\mathrm{mL}$of a $0.162\mathrm{M}\mathrm{NaOH}$solution is required to titrate $25.0\mathrm{mL}$of a solution of ${\mathrm{H}}_2{\mathrm{SO}}_4$, what is the molarity of the ${\mathrm{H}}_2{\mathrm{SO}}_4$solution?

${\mathrm{H}}_2{\mathrm{SO}}_4\left(aq\right)+2\mathrm{KOH}\left(aq\right)⟶2{\mathrm{H}}_2\mathrm{O}\left(l\right)+{\mathrm{K}}_2{\mathrm{SO}}_4\left(aq\right)$

If $38.2\mathrm{mL}$of a $0.163\mathrm{M}\mathrm{KOH}$solution is required to titrate $25.0\mathrm{mL}$of a solution of ${\mathrm{H}}_2{\mathrm{SO}}_4$, what is the molarity of the ${\mathrm{H}}_2{\mathrm{SO}}_4$solution$?$

${\mathrm{H}}_2{\mathrm{SO}}_4\left(aq\right)+2\mathrm{NaOH}\left(aq\right)⟶2{\mathrm{H}}_2\mathrm{O}\left(l\right)+{\mathrm{Na}}_2{\mathrm{SO}}_4\left(aq\right)$

Which of the following represents a buffer system? Explain.

a. $\mathrm{NaOH}$and$\mathrm{NaCl}$

b. ${\mathrm{H}}_2{\mathrm{CO}}_3$and${\mathrm{NaHCO}}_3$

c. $\mathrm{HF}$and$KF$

d. $\mathrm{KCl}$and$\mathrm{NaCl}$

Which of the following represents a buffer system? Explain.

a.$H_{3}P{O}_3$

b.localid="1654007245452" ${\mathrm{NaNO}}_3$

c.localid="1654007248599" ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2\text{and}{\mathrm{NaC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$

d.localid="1654007252192" $\mathrm{HCl}\text{and}\mathrm{NaOH}$

Consider the buffer system of hydrofluoric acid, HF, and its salt, NaF .

$\mathrm{HF}\left(aq\right)+{\mathrm{H}}_2\mathrm{O}\left(l\right)\rightleftarrows {\mathrm{H}}_3{\mathrm{O}}^{+}\left(aq\right)+{\mathrm{F}}^{-}\left(aq\right)$

a. The purpose of this buffer system is to:

1. maintain [HF]

2. maintain $\left[{\mathrm{F}}^{-}\right]$

3. maintain $\mathrm{pH}$

b. The salt of the weak acid is needed to:

1. provide the conjugate base

2. neutralize added ${\mathrm{H}}_3{\mathrm{O}}^{+}$

3. provide the conjugate acid

c. If ${\mathrm{OH}}^{-}$is added, it is neutralized by:

1. the salt

2. ${\mathrm{H}}_2\mathrm{O}$

3. ${\mathrm{H}}_3{\mathrm{O}}^{+}$

d. When${\mathrm{H}}_3{\mathrm{O}}^{+}$is added, the equilibrium shifts in the direction of the:

1. reactants

2. products

3. does not change

Consider the buffer system of nitrous acid, ${\mathrm{HNO}}_2$, and its salt, ${\mathrm{NaNO}}_2$.

${\mathrm{HNO}}_2\left(aq\right)+{\mathrm{H}}_2\mathrm{O}\left(l\right)\rightleftarrows {\mathrm{H}}_3{\mathrm{O}}^{+}\left(aq\right)+{\mathrm{NO}}_2^{-}\left(aq\right)$

a. The purpose of this buffer system is to:

1. maintain $\left[{\mathrm{HNO}}_2\right]$

2. maintain $\left[{{\mathrm{NO}}_2}^{-}\right]$

3. maintain $\mathrm{pH}$

b. The weak acid is needed to:

1. provide the conjugate base

2. neutralize added ${\mathrm{OH}}^{-}$

3. provide the conjugate acid

c. If ${\mathrm{H}}_3{\mathrm{O}}^{+}$is added, it is neutralized by:

1. the salt

2. ${\mathrm{H}}_2\mathrm{O}$

3. ${\mathrm{OH}}^{-}$

d. When ${\mathrm{OH}}^{-}$is added, the equilibrium shifts in the direction of the:

1. reactants

2. products

3. does not change

Why would the pH of your blood plasma increase if you breathe fast?

Write formulas for each of the following acids and bases:

a. barium hydroxide

b. hydroiodic acid

c. bromic acid

d. strontium hydroxide

e. acetic acid

f. hypochlorous acid