Calculate the change in pH when 7.00 mL of 0.100 M HCl(aq) is added to 100.0 mL of a buffer solution that is 0.100 M in NH3(aq) and 0.100 M in NH4Cl(aq). Using the original buffer solution, what would then be the change in pH when 7.00 mL of 0.100 M NaOH(aq) is added to the original buffer solution?