If you are given a mass of sodium lactate, NaCH3CHOHCO2 which is added to ---ml of a ---M solution of lactic aid, can you please just give me the equation
Give you the equation for what? Sodium lactate is the salt of a weak acid and a strong base and lactic acid is a weak acid. This COULD be a buffer solution. But it could be a lot of other stuff, too. If it's a buffer, the equation may be
pH = pKa + log (base/acid).