its me again this is how you find the answer. note: i dont have the periodic table to see the exact atomic mass to find the molar mass however this is the answer:
so the actual formula is Mg(OH) with a 2 as a subscript because there are 2 Mg. so with Mg(OH)2 the Molar mass is 58.32g/mol. 58.32 g/mol x 7.1x1024 = 4.1x1026g
