Acetylsalicylic acid, C9H8O4, is the pain reliever in many headache medications. A typical tablet contains 250.0 mg of acetylsalicylic acid.
(a) Calculate the amount of acetylsalicylic acid in the tablet.
(b) Calculate the number of hydrogen atoms in the amount of acetylsalicylic acid in the tablet determined in (a).

Phosphoric acid is a triprotic acid ( =6.9×10−3 , =6.2×10−8 , and =4.8×10−13 ). to find the ph of a buffer composed of h2po−4(aq) and hpo2−4(aq) , which p value should be used in the henderson–hasselbalch equation? p k a1 = 2.16 p k a2 = 7.21 p k a3 = 12.32 calculate the ph of a buffer solution obtained by dissolving 18.0 18.0 g of kh2po4(s) kh 2 po 4 ( s ) and 33.0 33.0 g of na2hpo4(s) na 2 hpo 4 ( s ) in water and then diluting to 1.00 l.