The K_sp of Ag₂CrO₄, AgCl, AgBr, and Agl are respectively, 1.1 × 10^–12, 1.8 × 10^–10, 5.0 × 10^–13, 8.3 × 10^–17. Which one of the following salts will precipitate last if ${\mathrm{AgNO}}_3$ solution is added to the solution containing equal moles of NaCl, NaBr, Nal, and Na₂CrO₄?

1. Agl

2. AgCl

3. AgBr

4. Ag₂CrO₄

For the reversible reaction:
N₂(g) + 3H₂(g) \(\rightleftharpoons\) 2NH₃(g) + heat 

The equilibrium shifts in a forward direction:

1. by increasing the concentration of $N{H}_3\left(g\right)$
2. by decreasing the pressure.
3. by decreasing the concentration of $N_2\left(g\right)$ $and$ $H_2\left(g\right)$
4. by increasing pressure and decreasing temperature.

Buffer solutions have constant acidity and alkalinity because:
 

A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of  $N{H}_4^{+ }$ is 0.20 M. If the equilibrium constant, K_b for NH₃ equals 1.8×10^–5, then what is the pH of this solution? 
(log 1.8 = 0.25; log 0.67 = –0.176)

1.  9.43
2.  11.72
3.  8.73
4.  9.08

The value of $∆\mathrm{H}$ for the reaction is less than zero. Formation of $X_2\left(g\right)$ $+$ $4$ $Y_2\left(g\right)$ $\leftrightharpoons 2X{Y}_4\left(g\right)$ will be favoured at:

For the reaction ${\mathrm{N}}_2\left(\mathrm{g}\right)$ $+$ ${\mathrm{O}}_2\left(\mathrm{g}\right)\leftrightharpoons 2\mathrm{NO}\left(\mathrm{g}\right)$ the equilibrium constant is K₁. The equilibrium constant is K₂ for the reaction  $2\mathrm{NO}\left(\mathrm{g}\right)$ $+$ ${\mathrm{O}}_2\left(\mathrm{g}\right)$ $\leftrightharpoons 2{\mathrm{NO}}_2\left(\mathrm{g}\right)$ $$
The value of K for the reaction given below will be:
${\mathrm{NO}}_2\left(\mathrm{g}\right)\leftrightharpoons \frac{1}{2}{\mathrm{N}}_2\left(\mathrm{g}\right)$ $+{\mathrm{O}}_2\left(\mathrm{g}\right)$ $$

1.  $\frac{1}{4}$ $\left(4\right)$ ${\mathrm{K}}_1$ ${\mathrm{K}}_2$

2.  ${\left[\frac{1}{{\mathrm{K}}_1{\mathrm{K}}_2}\right]}^{1/2}$

3.  $\frac{1}{\left({\mathrm{K}}_1{\mathrm{K}}_2\right)}$

4.  $\frac{1}{\left(2{\mathrm{K}}_1{\mathrm{K}}_2\right)}$

What is [H⁺] in mol/L of a solution that is 0.20 M in CH₃COONa and 0.10 M in CH₃COOH ?(K_a  for CH₃COOH = 1.8 x 10^-5):
1. \(3 . 5 \times \left(10\right)^{- 4}\)
2. \(1 . 1 \times \left(10\right)^{- 5}\)
3. \(1 . 8 \times \left(10\right)^{- 5}\)
4. \(9 . 0 \times \left(10\right)^{- 6}\)${\mathrm{}}^{}$

The equilibrium reaction that doesn't have equal values for K_c and K_p is: 

1. \(2NO(g) \rightleftharpoons N_2(g) + O_2(g)\)
2. \(SO_2(g) + NO_2(g) \rightleftharpoons SO_3(g) + NO(g)\)
3. \(H_2(g) + I_2(g) \rightleftharpoons 2HI (g)\)
4. \(2C(s) + O_2(g) \rightleftharpoons 2CO_2(g)\)

In a buffer solution containing an equal concentration of B^- and HB, the K_b for B^- is 10^-10. pH of the buffer solution is:

Which of the following molecular hydrides acts as a Lewis acid?

1. $N{H}_3$

2. $H_{2}O$

3. $B_2{H}_6$

4. $C{H}_4$