A 40 years old male develops excessive hyperven-tilation. A G reveals pH- 7.5 pCO2 24 mm Hg PO2 88 mm of Hg. True statement is -: (A) Respiratory alkalosis, (B) Metabolic alkalosis, (C) Respiratory acidosis, (D) Metabolic acidosis
Answer is A. First step

Determine whether it is acidosis or alkalosis
Increased pH indicates alkalosis

Second step

Inspect HCO3-/CO2 to determine the cause of alkalosis or acidosis.

pCO2 → 24 mm Hg (decreased)

The alteration in CO2 is in sync. with the alteration in the pH, so the alkalosis can be attributed to a decrease in pCO2.
Thus, it is a case of respiratory alkalosis.