Question

Which phosphate equilibrium reaction is acting as a buffer at the high pH area?

a) Clearly define the concept of a buffer in a chemical system, emphasizing its role in maintaining pH stability.
b) Present the relevant phosphate equilibrium reactions, specifying the chemical species involved and their transformations.
c) Identify the specific phosphate equilibrium reaction that functions as a buffer at the high pH area.

Ensure clarity in your question to elicit a precise identification of the buffer reaction and a comprehensive understanding of its role in pH regulation.

Answer 1

The specific phosphate equilibrium reaction that functions as a buffer at high pH is the reaction between HPO4²⁻ and H₂O to form H₂PO4⁻ and OH⁻.

Step-by-step explanation:

A buffer is a chemical system that helps maintain a stable pH by resisting changes in pH when an acid or a base is added. Buffers contain a weak acid and its conjugate weak base. One of the key buffer systems in biochemical systems is the CO₂/HCO3 system, which is dominant in blood plasma. The specific phosphate equilibrium reaction that functions as a buffer at high pH is:

HPO4²⁻(aq) + H₂O(l) ⇌ H₂PO4⁻(aq) + OH⁻(aq)