Question

Fear or excitement generally causes one to breathe rapidly and it results in a decrease in ${\mathrm{CO}}_2$ concentration in the blood. In what way will it change the pH of blood?

• A. pH will increase
• B. pH will decrease
• C. No change
• D. pH will be 7

Answer 1

The correct option is C

No change

Explanation of the correct option:

The correct answer is option C:

• A weak acid and the conjugate base of the weak acid, or a weak base and the conjugate acid of the weak base, are combined to form the buffer solution, a water-based solvent solution.
• They withstand being diluted or having modest amounts of acid or alkali added to them without changing their pH.
• Since blood is a buffer solution, its pH will not change when ${\mathrm{CO}}_2$ concentration changes and will remain constant.
• A serum protein in it serves as a buffer.

Explanation of the incorrect options:

1. When there is a decrease in ${\mathrm{CO}}_2$ concentration in the blood, there will be no change in the pH of the blood.
2. Thus, these options are incorrect.

Hence, option C is correct, i.e., no change.