A certain metal hydroxide, M(OH)2 contains 32.8% oxygen by mass. What is the identity of the metal M? I don't understand what its asking for.

Answer 1

You know the percent of O, so the percent of H is 1/16 of that, then you know the percent of M.

Knowing the percent of M, and the percent of 20's, you can determine the atomic mass of M.

MassatomicM/percentM=massatomic20/percentO

You know the atomic mass of M, and that it is in group II, you have....