Question

Freediving is an activity in which a person dives, sometimes to great depth, without the use of scuba gear. the diver must hold his or her breath for the duration of the dive. (the record depth, with no equipment such as diving fins, is 101 m; the official record time is over 11 minutes.) historically, freediving has been used by pearl divers and sponge divers. some freedivers hyperventilate (breathe rapidly and deeply) before diving. hyperventilation can change the concentration of co2 in the blood and may inc

Answer 1

Hyperventilation affect blood pH by decreasing the carbon dioxide in the blood  and increasing H+ in the blood thus increasing pH.
Carbon dioxide react with water to form carbonic acid in the body, thus an increase in carbon dioxide result in decrease in blood pH. Decrease in carbon dioxide level in the blood result in increase in the pH of the blood, this makes hemoglobin to pick up more oxygen.