Which of the following solution(s) have pH between 6 and 7?
I. \(2 \times 10^{-6}~ \text {M NaOH}\)
II. \(2 \times 10^{-6}~ \text {M HCl}\)
III. \( 10^{8}~ \text {M HCl}\)
IV. \(10^{-13}~ \text {M NaOH}\)

1. I, II
2. III only
3. III, IV
4. II, III, IV

At what pH does Mg(OH)₂ start to precipitate from a solution with 0.10 M Mg²⁺ ions, given that the Ksp of Mg(OH)₂ is 1 × 10⁻¹¹?

1. 3

2. 6

3. 9

4. 11

50 litres of 0.1 M HCl are mixed with 50 litres of 0.2 M NaOH. The pH of the resulting solution will be:

1. 12.70

2. 12.34

3. 8.7

4. 4.2

The pH of a 0.05 M aqueous solution of diethylamine is 12. Its K_b value will be:

1. $2\times {10}^{-3}$

2. $2.5\times {10}^{-3}$

3. $3\times {10}^{-3}$

4. $4.5\times {10}^{-3}$

K_a for HCN is $5\times {10}^{-10}$ at $25°\mathrm{C}$. For maintaining a constant pH of 9, the volume of 5 M KCN solution required to be added to 10 mL of 2 M HCN solution is-

1. 2 mL

2. 3 mL

3. 4.2 mL

4. 5.6 mL

The approximate pH of a solution formed by mixing equal volumes of solutions of 0.1 M sodium propionate and 0.1 M propanoic acid (the dissociation constant of propanoic acid is \(1.3 \times 10^{-5}~ \text {mol dm}^{-3}\)${\mathrm{}}^{}$)  will be:

The dissociation constant of acetic acid is \(1 . 6 \times 10^{- 5}\). The degree of dissociation \(\left(\right. \alpha \left.\right)\) of 0.01 M acetic acid in the presence of 0.1 M HCl is equal to: 

1. \(1.6 \times 10^{-3}\)
2. \(1.6 \times 10^{-1}\)
3. \(1.6 \times 10^{-6}\)
4. \(1.6 \times 10^{-4}\)

If the equilibrium constant of the reaction of weak acid HA with strong base is 10⁹, then pH of 0.1 M NaA is:

If Ksp of Al(OH)₃ is $1.0\times {10}^{-15}<mspace\; width="1em"></mspace>\mathrm{M}.$ Find at what pH does $1.0\times {10}^{-3}<mspace\; width="1em"></mspace>\mathrm{M}$ Al³⁺ precipitate on the addition of buffer of NH₄Cl and NH₄OH solution.

1. 10

2. 10.5

3. 11

4. 12

The solubility of CaF₂ in water at 298 K is $1.7\times {10}^{-3}$ gm per 100 cm³. The solubility product of CaF₂ at 298 K is :

1. $4.14\times {10}^{-11}$

2. $4.14\times {10}^{11}$

3. $4.14\times {10}^{-6}$

4. $4.14\times {10}^6$