Prepare a 250-mL buffer with pH=4.40 from solid reagents benzoic acid (C6H5COOH: M= XXXXXXXXXXg mol-1) and sodium benzoate (C6H5COONa:M= XXXXXXXXXXg mol-1). The pKa for potassium dihydrogen phosphate...

Prepare a 250-mL buffer with pH=4.40 from solid reagents benzoic acid (C6H5COOH: M= 122.123 g mol-1) and sodium benzoate (C6H5COONa:M=144.105 g mol-1). The pKa for potassium dihydrogen phosphate is 4.202. What is the balanced equation showing the equilibrium of the buffer solution