A buffer solution contains carbonic acid (H₂CO₃)and sodium bicarbonate (NaHCO₃),each at a concentration of 0.100 M.The relevant equilibrium is shown below.What is the pH of this buffer solution? H₂CO₃(aq)+ H₂O(l) ? H₃O⁺(aq)+ HCO₃^?(aq)K_a = 4.5 × 10^?7

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The pH of the buffer solution can be calculated using the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]), where [A-] is the concentration of the conjugate base (sodium bicarbonate, NaHCO3) and [HA] is the concentration of the acid (carbonic acid, H2CO3). Given that both are at 0.100 M and the Ka = 4.5 × 10^-7 (thus pKa = -log(4.5 × 10^-7) ≈ 6.35), the pH = 6.35 + log(1) = 6.35, because log(1) = 0.

A Buffer Solution Contains Carbonic Acid (H2CO3)and Sodium Bicarbonate (NaHCO3),each

A Buffer Solution Contains Carbonic Acid (H₂CO₃)and Sodium Bicarbonate (NaHCO₃),each