Question

Consider a solution consisting of the following two buffer systems:

Answer 1

Answer:

Option (e) is correct

Explanation:

According to Henderson - hasel balch equation

For H₂CO₃ / HCO₃⁻

$pH = pka + log\frac{[HCO^-_3]}{[H_2CO_3]} \\\\= 6.4 + log\frac{[HCO^-_3]}{[H_2CO_3]} -------(1)$

For H₂PO₄⁻ / HPO₄²⁻

$pH = pka + log\frac{[HPO_4^2^-]}{[H_2PO_4^-]} \\\\= 7.2 + log\frac{[HPO_4^2^-]}{[H_2PO_4^-]}-----(2)$

Now ph for buffer mixture is 6.4

pH = 6.4 in eqn(1) [HCO₃⁻]- [H₂CO₃]

pH = 6.4 in eqn(2) [H₂PO₄⁻] > [HPO₄²⁻]

Option (e) is correct