Let us write succinic acids as H2Suc The first ionization is H2Suc ----> HSuc- + H+ The seond ionization is HSuc- ----> Suc-2 + H+ Calculate the H+ concentration of from the first ionization using pKa1. Then, calculate the H+ concentration from the second ionization using pKa2. Next, use the buffer equation to calculate the concentration of the salt in the solution. Then, use the given volume to get the number of moles of the salt. Finally, use the given molecular weight to get the mass.
The molarity of a solution equals to the mole number of the solute/the volume of the solution. For NH4Br, we know that the mole mass is 98. So the molarity is (14/98) mol /0.15 L=0.95 mol/L.
