Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value?

1.	\(\mathrm{B a C l_{2}}\)	2.	\(\mathrm{A l C l_{3}}\)
3.	\(\mathrm{L i C l}\)	4.	\(\mathrm{B e C l_{2}}\)

A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of  $N{H}_4^{+\hspace{0.17em}}$ 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

What conditions favor the formation of 2XY₄(g) in the reaction X₂(g) + 4Y₂(g) ⇋ 2XY₄(g), considering that the enthalpy change (ΔH) is negative?

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:

The tendency of BF₃, BCl₃ and BBr₃ to behave as Lewis acid decreases in the sequence:

1. $BC{l}_3>B{F}_3>BB{r}_3$

2. $BB{r}_3>BC{l}_3>B{F}_3$

3. $BB{r}_3>B{F}_3>BC{l}_3$

4. $B{F}_3>BC{l}_3>BB{r}_3$

The ionization constant of ammonium hydroxide is 1.77 x 10^-5 at 298 K. Hydrolysis constant of ammonium Chloride is:

1. 5.65 x 10^-10

2. 6.50 x 10^-12

3. 5.65 x 10^-13

4. 5.65 x 10^-12

If the concentration of OH ' ions in the reaction