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

Calculate the hydrogen ion concentration, [\(\text{H}^+\)] (in \(\text{mol}/\text{L}\)), of a buffer solution prepared by mixing \(0.10 \text{ M}\) acetic acid (\(\text{CH}_3\text{COOH}\)) and \(0.20 \text{ M}\) sodium acetate (\(\text{CH}_3\text{COONa}\)), given that the acid dissociation constant (\(\text{K}_a\)) for acetic acid is \(1.8 \times 10^{-5}\):

1. \(3 . 5 \times 10^{- 4}\)
2. \(1 . 1 \times 10^{- 5}\)
3. \(1 . 8 \times 10^{- 5}\)
4. \(9 . 0 \times10^{- 6}\)${\mathrm{}}^{}$

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. $C{H}_4$

What is the [OH^-] in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M Ba(OH)₂?

1. 0.10 M

2. 0.40 M

3. 0.0050 M

4. 0.12 M

The dissociation constants for acetic acid and HCN at 25 °C are 1.5 x 10^-5 and 4.5 x 10^-10, respectively. The equilibrium constant for the equilibrium, 
CN^- + CH₃COOH  ⇌  HCN + CH₃COO^- 
would be:
1. $3.0\times {10}^5$
2. $3.0\times {10}^{-5}$
3. $3.0\times {10}^{-4}$
4. $3.0\times {10}^4$

Equal volumes of three acid solutions of pH 3, 4 and 5 are mixed in a vessel. What will be the H⁺ ion concentration in the mixture?
1. $1.11\times {10}^{-4}$ $\mathrm{M}$
2. $3.7\times {10}^{-4}$ $\mathrm{M}$
3. $3.7\times {10}^{-3}$ $\mathrm{M}$
4. $1.11\times {10}^{-3}$ $\mathrm{M}$

The value of the equilibrium constant of the reaction 
 $\mathrm{HI}\left(\mathrm{g}\right)$ $\leftrightharpoons$ $\frac{1}{2}{\mathrm{H}}_2\left(\mathrm{g}\right)$ $+$ $\frac{1}{2}{\mathrm{I}}_2$ is 8.0.
The equilibrium constant of the reaction
 ${\mathrm{H}}_2\left(\mathrm{g}\right)$ $+$ ${\mathrm{I}}_2\left(\mathrm{g}\right)$ $\leftrightharpoons$ $2\mathrm{HI}\left(\mathrm{g}\right)\hspace{0.17em}$ will be-