Question
Question: Find out the osmotic pressure of 0.1 M monobasic acid, if pH = 2.0 at 25°C....
Find out the osmotic pressure of 0.1 M monobasic acid, if pH = 2.0 at 25°C.
A
2.69 atm
B
26.9 atm
C
0.269 atm
D
None of these
Answer
2.69 atm
Explanation
Solution
Solution Explanation:
- For a monobasic acid with concentration 0.1 M and pH 2.0, the [H⁺] concentration is 0.01 M.
- Degree of dissociation, x = [H⁺]/C = 0.01/0.1 = 0.1.
- The van’t Hoff factor, i = 1 + x = 1.1.
- Osmotic pressure, π = i·C·R·T.
- At 25°C, T = 298 K and using R = 0.0821 L·atm/(mol·K),
π = 1.1 × 0.1 × 0.0821 × 298
= 1.1 × 0.1 × 24.466
= 2.691 atm ≈ 2.69 atm.