Chapter 13

Is a saline ( $\mathrm{NaCl}$ ) solution at ${80}^{\circ }\mathrm{C}$ acidic, basic, or neutral?

Which of the following is/are true about a $0.10\mathrm{M}$ solution of a strong acid, HY? (a) $\left[{\mathrm{Y}}^{-}\right]=0.10\mathrm{M}$ (b) $[\mathrm{HY}]=0.10\mathrm{M}$ (c) $\left[{\mathrm{H}}^{+}\right]=0.10\mathrm{M}$ (d) $\mathrm{pH}=1.0$ (c) $\left[{\mathrm{H}}^{+}\right]+\left[{\mathrm{Y}}^{-}\right]=0.20\mathrm{M}$

Consider the following six beakers. All have $100\mathrm{mL}$ of aqueous $0.1\mathrm{M}$ solutions of the following compounds: beaker A has HI beaker B has ${\mathrm{HNO}}_2$ beaker $\mathrm{C}$ has $\mathrm{NaOH}$ beaker $\mathrm{D}$ has $\mathrm{Ba}(\mathrm{OH}{)}_2$ beaker $\mathrm{E}$ has ${\mathrm{NH}}_4\mathrm{Cl}$ beaker $\mathrm{F}$ has ${\mathrm{C}}_2{\mathrm{H}}_5{\mathrm{NH}}_2$

What is the $\mathrm{pH}$ of a $0.200\mathrm{M}$ solution of ${\mathrm{H}}_2{\mathrm{SO}}_4$ ? You may assume that the first ionization is complete. The second ionization constant is $0.010$.

Using the Tables in Appendix 1, calculate $\mathrm{\Delta }H$ for the reaction of the following. (a) $1.00\mathrm{L}$ of $0.100\mathrm{M}\mathrm{NaOH}$ with $1.00\mathrm{L}$ of $0.100\mathrm{M}\mathrm{HCl}$ (b) $1.00\mathrm{L}$ of $0.100\mathrm{M}\mathrm{NaOH}$ with $1.00\mathrm{L}$ of $0.100\mathrm{M}$ HF, taking the heat of formation of $\mathrm{HF}(aq)$ to be $-320.1\mathrm{kJ}/\mathrm{mol}$

Show by calculation that when the concentration of a weak acid decreases by a factor of 10 , its percent ionization increases by a factor of ${10}^{1/2}$.

What is the freezing point of vinegar, which is an aqueous solution of $5.00\mathrm{\%}$ acetic acid, ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$, by mass $(d=1.006\mathrm{g}/{\mathrm{cm}}^3)?$

The solubility of $\mathrm{Ca}(\mathrm{OH}{)}_2$ at ${25}^{\circ }\mathrm{C}$ is $0.153\mathrm{g}/100\mathrm{g}{\mathrm{H}}_2\mathrm{O}$. Assuming that the density of a saturated solution is $1.00\mathrm{g}/\mathrm{mL}$, calculate the maximum $\mathrm{pH}$ one can obtain when $\mathrm{Ca}(\mathrm{OH}{)}_2$ is dissolved in water.