Question

A) As a technician in a large pharmaceutical research firm, you need to produce 100. mL of 1.00 mol L−1 potassium phosphate buffer solution of pH = 6.78. The pKa of H2PO4− is 7.21. You have the following supplies: 2.00 L of 1.00 mol L−1 KH2PO4 stock solution, 1.50 L of 1.00 mol L−1 K2HPO4stock solution, and a carboy of pure distilled H2O. How much 1.00 mol L−1 KH2PO4 will you need to make this solution?

The Henderson–Hasselbalch equation in medicine - Carbon dioxide (CO2) and bicarbonate (HCO3−) concentrations in the bloodstream are physiologically controlled to keep blood pH constant at a normal value of 7.40. Physicians use the following modified form of the Henderson–Hasselbalch equation to track changes in blood pH: pH=pKa+log[HCO3−](0.030)(PCO2) where [HCO3−] is given in millimoles/litre and the arterial blood partial pressure of CO2 is given in mmHg. The pKa of carbonic acid is 6.1. Hyperventilation causes a physiological state in which the concentration of CO2 in the bloodstream drops. The drop in the partial pressure of CO2 constricts arteries and reduces blood flow to the brain, causing dizziness or even fainting.

B) If the normal physiological concentration of HCO3− is 24 mmol L−1, what is the pH of blood if PCO2 drops to 20.0 mmHg?

Please show work! Thank you!!

Answer 1