Determine the mass of gallium oxide when 14.5 g of gallium reacts with excess oxygen?

Question

Any help would be awesome in tryin gto understand this.

Answer 1

4 Ga & 3 O2 --> 2 Ga2O3

Galium III oxide, has 2 moles of Gallium @ 72.61 g/mol , making 1 mole of Ga2O3 @ 187.44 g/mol

using those molar masses:

14.5 g Ga @ 187.44 g/mol Ga2O3 / (2)(72.61g/mol Ga)=

your answer of 18.7 grams of Gallium III oxide