1. The problem statement, all variables and given/known data A certain metal hydroxide, M(OH)2, contains 32.8% oxygen by mass. What is the identity of the metal M? 2. Relevant equations O = 16.00 g x2 H = 1.008 g x2 3. The attempt at a solution I thought that 1g = 1% of the mass because there are 32g of O and it composed of 32.8% of O. So then I thought it would be around 2% of H. Then I added 32.8% + 2% and subtracted it from 100%. This was supposely my answer. I thought it was Zinc and it was wrong.
You are not completely off, but you have to do your calculations using exact value of the oxygen percentage. --