16. explain hov
to explain how (in terms of a shift in reaction rates in response to putting a chemical stress on the system) the
following equilibrium buffer system in human blood maintain homeostatic ph levels:
co2 + h20 --> h2co3 -> h+ + hco3

See below

Explanation:

According to Le Châtelier's Principle, when a stress is applied to a system at equilibrium, the system will respond in a way that tends to relieve the stress.

(i) Increasing [H⁺]

If [H⁺] increases, the rate of the reaction with HCO₃⁻ increases, so the rate of formation of H₂CO₃ is greater than the rate of ionization.

The increased concentration of H₂CO₃ causes its rate of decomposition to increase, and more CO₂ is expelled to the atmosphere.

(ii) Decreasing [H⁺]

If [H⁺] decreases, the rate of the reaction with HCO₃⁻ decreases, so the rate of ionization of H₂CO₃ is faster than the reverse reaction.

The decreased concentration of H₂CO₃ causes its rate of decomposition to CO₂ to decrease. The rate of formation of H₂CO₃ from CO₂ is greater than the rate of decomposition.

The net effect is that CO₂ is absorbed into the blood.