All the info I have is the % of metal (52,9411%). I need to identify the oxide and find a thermal decomposition reaction with oxide as a product. This is all I could do:

%_{oxygen}= 100 – 52,9411 = 47,0589

M_{2}O_{n} = the oxide

A_{M} = the atomic mass of the metal

n = the valence of the metal

(2 x A_{M} x 100)/(2 x A_{M}+n x 16 )=52,9411 % Metal

200 x A_{M} = 105,8822 x A_{M} + 847,0576 x n

(16 x n x 100)/(2 x A_{M}+n x 16 )=47,0589 % Oxygen

1600 x n = 94,1178 x AM + 847,0576 x n

94,1178 x A_{M} = 847,0576 x n

A_{M} = 9 x n