Calculate the pH after 0.10 mol of NaOH is added to 1.0 L of a solution that is 0.40 M CH3NH2 and 0.80 M CH3NH3Cl. WebAssign will check your answer for the correct number of significant figures. Calculate the pH after 0.10 mol of HCl is added to 1.0 L of a solution that is 0.40 M CH3NH2 and 0.80 M CH3NH3Cl. WebAssign will check your answer for the correct number of significant figures.