Part 1
Calculate the acidity constant of benzoic acid in water at 298K if Delta Gf for C6H5CO2-(aq) is -269.2 kj/mol and delta Gf for C6H5COOH(aq) is -293.1 kj/mol. (The Delta Gf has a degree symbol on it if that is needed.)
Part 2
What mass of sodium benzoate must be added to 3 L of 1.1 M C6H5COOH(aq) to make a buffer with pH=3? Answer in units of g.
Provide your answer in scientific notation