SDN Members don't see this ad. (About Ads) Hi, i need help on this question! so it asks "which of the following pairs of compounds could be mixed to produce a buffer solution?" one of the answer choice is CH3NH2 and CH3NH3I which is the answer. The answer key explains that it works since it consists of weak base methyl amine and conjugate base methylammoniumiodide. I dont really understand why CH3NH3I is the conjugate base...for some reason, i thought it is a conjugate acid. can someone clarify on this? thanx!!!