As a technician in a large pharmaceutical research firm, you need to produce 400. ml of 1.00 mol l−1 potassium phosphate buffer solution of ph = 7.08. 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 k2hpo4 stock solution, and a carboy of pure distilled h2o. how much 1.00 mol l−1 kh2po4 will you need to make this solution? socratic. org?