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 CO, in the blood and may increase the length of time that a person feels like he or she can hold his or her breath. How does hyperventilation affect blood pH?
It decreases CO, and increases Ht in the blood, decreasing pH.
It decreases Co, and H+ in the blood, increasing pH.
It increases CO, and decreases H+ in the blood, increasing pH.
It increases CO, and Ht in the blood, decreasing pH.

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.