Methylamine, CH3NH2, is a weak base. The value of the ionization constant, Kb, is 5.25x10-4. Methylamine forms salts such as methylammonium nitrate, (CH3NH3+)(NO3-).
(a) Calculate the hydroxide ion concentration, [OH-], of a0.225-molar aqueous solution of methylamine.answer: 1.1 E -2
(b) Calculate the pH of a solution made by adding 0.0100 mole of solid methylammonium nitrate to 120.0 milliliters of a0.225-molar solution of methylamine. Assume no volume change occurs.answer: 9.39
(c) How many moles of either NaOH or HCl (state clearly whichyou choose) should be added to the solution in (b) to produce asolution that has a pH of 11.00? Assume that no volume change occurs.answer: 0.001mol of HCL
(d) A volume of 100. milliliters of distilled water is addedto the solution in (c). How is the pH of the solution affected?