chemistry help please

Question

Fred and Daphne went to a concert of the latest pop group. When the lead singer threw his ascot to Daphne, she started hyperventilating and then passed out. Is Daphne suffering from respiratory acidosis or alkylosis? And what is happening to the blood pH and CO₂ levels of each.

A. Alkylosis; pH increases; CO₂ decreases

B.   Acidosis; pH increases; CO₂ decreases

 C.  Alkylosis; pH increases; CO₂ increases

D.   Alkylosis; pH decreases; CO₂ increases

E.   Acidosis; pH decreases; CO₂ increases

Answer 1

First thing we want to consider are the effects of hyperventilating - excessive ventilation of carbon dioxide. Due to the increased amount of CO2 being exhaled, PCO2 (CO2 levels in blood) decreases.

Recall the carbonic acid-bicarbonate buffer system (which regulates pH of the blood): 

CO₂ + H₂O ↔ H₂CO₃ ↔ H⁺ + HCO₃^-

A decrease in CO2 concentration will cause the carbonic acid/bicarbonate equilibrium to shift left. The resulting decrease in H+ concentration leads to an increase in pH.

To wrap it all up, pH increases and CO2 decreases - this only corresponds to answer choice A or B. Since we are talking about an INCREASE in pH, acidosis doesn’t make sense. Therefore, answer choice A is correct.