Chapter 17

For the reaction $${\mathrm{N}}_2(g)+3{\mathrm{H}}_2(g)\rightleftharpoons 2{\mathrm{NH}}_3(g)$$ $K=1.3\times {10}^{-2}$ at a given temperature. If the system at equilibrium is analyzed and the concentrations of both ${\mathrm{N}}_2$ and ${\mathrm{H}}_2$ are found to be $0.10\mathrm{M},$ what is the concentration of ${\mathrm{NH}}_3$ in the system?

The equilibrium constant for the reaction $$2\mathrm{NOCl}(g)\rightleftharpoons 2\mathrm{NO}(g)+{\mathrm{Cl}}_2(g)$$ has the value $9.2\times {10}^{-6}$ at a particular temperature. The system is analyzed at equilibrium, and it is found that the concentrations of $\mathrm{NOCl}(g)$ and $\mathrm{NO}(g)$ are $0.44\mathrm{M}$ and $1.5\times {10}^{-3}M,$ respectively. What is the concentration of ${\mathrm{Cl}}_2(g)$ in the equilibrium system under these conditions?

As you learned in Chapter 7 , most metal hydroxides are sparingly soluble in water. Write balanced chemical equations describing the dissolving of the following metal hydroxides in water. Write the expression for $K_{\mathrm{sp}}$ for each process. a. $\mathrm{Cu}(\mathrm{OH}{)}_2(s)$ b. $\mathrm{Cr}(\mathrm{OH}{)}_3(s)$ c. $\mathrm{Ba}(\mathrm{OH}{)}_2(s)$ d. $\mathrm{Sn}(\mathrm{OH}{)}_2(s)$

The three common silver halides ( $\mathrm{AgCl},\mathrm{AgBr},$ and $\mathrm{AgI}$ ) are all sparingly soluble salts. Given the values for $K_{\mathrm{sp}}$ for these salts below, calculate the concentration of silver ion, in $\mathrm{mol}/\mathrm{L},$ in a saturated solution of each salt.

Approximately $9.0\times {10}^{-4}\mathrm{g}$ of silver chloride, $\mathrm{AgCl}(s),$ dissolves per liter of water at 10 ' $\mathrm{C}$. Calculate $K_{\mathrm{sp}}$ for $\mathrm{AgCl}(s)$ at this temperature.

Mercuric sulfide, $\mathrm{HgS},$ is one of the least soluble salts known, with $K_{\mathrm{sp}}=1.6\times {10}^{-54}$ at 25 ?. Calculate the solubility of $\mathrm{HgS}$ in moles per liter and in grams per liter.

Approximately $0.14\mathrm{g}$ of nickel(II) hydroxide, $\mathrm{Ni}(\mathrm{OH}{)}_2(s),$ dissolves per liter of water at 20 ' $\mathrm{C}$. Calculate $K_{\mathrm{sp}}$ for $\mathrm{Ni}(\mathrm{OH}{)}_2(s)$ at this temperature.

What does the activation energy for a reaction represent? How is the activation energy related to whether a collision between molecules is successful?

What are the catalysts in living cells called? Why are these biological catalysts necessary?

When a reaction system has reached chemical equilibrium, the concentrations of the reactants and products no longer change with time. Why does the amount of product no longer increase, even though large concentrations of the reactants may still be present?