Question

When 0.1 mole of an acid is added to 2 L of a buffer solution, the pH of the buffer decreases by 0.5. The buffer capacity of the solution is

• A. 0.6
• B. 0.4
• C. 0.2
• D. 0.1

Answer 1

Answer: (D)

0.1

Answer 2

Buffer capacity $\text{=}\frac{\text{number}\,\text{of moles of acid added/L}}{\text{change in pH}}$ Given, number of moles of add added/L $=\frac{0.1}{2}$ Change in $pH=0.5$ Buffer capacity $=\frac{0.1}{2\times 0.5}=\frac{0.1}{1}=0.1$