Which among the following acids is the strongest, based on their given pKa values?

(I) 4.0

(II) 3.5

(III) 2.5

(IV) 2.0

1. I.0

2. II

3. III

4. IV

A solution has hydrogen ion concentration 0.0005 M, its pOH is:

1. 8.2798

2. 10.6990

3. 12.7854

4. 13.3344

At 25°C, the pH of a solution containing 0.10 M sodium acetate and 0.03 M acetic acid will be:

[pK_a value of ${\mathrm{CH}}_3\mathrm{COOH}=4.57$]

1. 3.24

2. 4.59

3. 5.09

4. 6.67

Ionization constant of acetic acid(\(\mathrm{CH}_3 \mathrm{COOH}\)) is $1.8\times {10}^{-5}$. The concentration of H⁺ ions in 0.1 M solution is:

1. $1.8\times {10}^{-3}<mspace\; width="1em"></mspace>\mathrm{M}$

2. $2.8\times {10}^{-3}<mspace\; width="1em"></mspace>\mathrm{M}$

3. $1.3\times {10}^{-3}<mspace\; width="1em"></mspace>\mathrm{M}$

4. $1.34\times {10}^{-4}<mspace\; width="1em"></mspace>\mathrm{M}$

What is the ionization percentage for a weak acid with a dissociation constant of \(4.9×10^{−8}\) at 0.1 M concentration?

Find the degree of dissociation (α) of a 0.1 M weak monoprotic acid HA if the pH of its solution is 3.

1. 1.0%

2. 10%

3. 50%

4. 25%

Find the pH of the solution obtained by mixing 75 mL of 0.2 M HCl with 25 mL of 1.0 M HCl
and then adding 300 mL of distilled water.

1. 1.0

2. 2.0

3. 4.0

4. 0.2

The dissociation constants of two acids HA₁ and HA₂ are $3.0\times {10}^{-4}$ and $1.8\times {10}^{-5}$ respectively. The relative strengths of the acids is:

1. 1:16

2. 1:4

3. 4:1

4. 16:1

Find the percentage ionization of a weak acid in a 0.005 M solution that has a pH of 5.

1. 0.8%

2. 0.6%

3. 0.4%

4. 0.2%

100 ml of 0.015 M HCl solution is mixed with 100 ml of 0.005 M HCl. What is the pH of the resultant solution?

1. 2.5

2. 1.5

3. 2

4. 1