Methylamine, CH3NH2, is a weak base. The value of theionization constant, Kb, is 5.25x10-4. Methylamine forms salts suchas methylammonium nitrate, (CH3NH3+)(NO3-).
(a) Calculate the hydroxide ion concentration, [OH-], of a0.225-molar aqueous solution of methylamine.
(b) Calculate the pH of a solution made by adding 0.0100 moleof solid methylammonium nitrate to 120.0 milliliters of a0.225-molar solution of methylamine. Assume no volume changeoccurs.
(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 changeoccurs.
(d) A volume of 100. milliliters of distilled water is addedto the solution in (c). How is the pH of the solution affected?Explain.