Question

a 5.55g sample of a weak acid with ka=1.3*10^-4 was combined with 5.00ml of 6.00 M NAOH and the resulting solution was diluted to 750mL. The measured pH of the solution was 4.25. what is the molor mass of the weak acid.
if used the formula
pH=kpa+log(base/acid)
Ph=3.89+log(6.00/x)
(x)=2.62
i don't know how to find the molar mass

14 years ago