If NaOH a strong base is added to the blood which of the fol

If NaOH, a strong base, is added to the blood, which of the following occurs? Bicarbonate will bind OH- Carbonic acid will bind OH- Carbonic acid will release H+ Carbonic acid will bind H+ Explain your reasoning here:

Solution

Correct option .C.

Ans. NaOH is a strong base. It dissociates into Na⁺ and OH^- ions in aqueous system (here, blood).

Blood exhibits buffering activity due to bicarbonate buffer system in it. It consists of carbonic acid (CO₂ + H₂O Û H₂CO₃ – a reversible reaction catalyzed by carbonic anhydrase) and bicarbonate ion as central components.

            CO₂ + H₂O <=====> H₂CO₃ <=======> HCO₃^- + H⁺            - bicarbonate buffer system – equation 1

Option A: Incorrect.

            Bicarbonate ion (HCO₃^-) can’t bind to OH^-. It can only bind to H⁺ ions. See stoichiometry of equation 1.

Option B: Incorrect.

            Carbonic acid (H₂CO₃) can’t bind to OH^-. See stoichiometry of equation 1.

Option C: Correct.

            Carbonic acid (H₂CO₃) will release H⁺ ions. The resultant protons bind with OH^- produced from NaOH and neutralize it by forming a water molecule.

            H⁺ (from carbonic acid) + OH^- (from NaOH) ------> H₂O     (Neutralized)

Thus, carbonic acid neutralizes NaOH.

Option D: Incorrect.

            Carbonic acid (H₂CO₃) can’t bind to H⁺. See stoichiometry of equation 1.