Chemistry question

Question

The atomic molar mass of a hypothetical element X is 100 u. It is found that the 50.0 g of X combines with 32.0 g of oxygen. What is the simplest formula for the oxide of X?

Atomic Molar Mass of Oxygen: 16.0 g/mol

(A) Х2O

(B)XO2

(C) X2O3

(D) XO4

Answer 1

atomic mass X = 100

atomic mass oxygen = 16

50.0 g X * 1 mol X / 100 g = 0.5 mols X

32 g O * 1mol O / 16 g = 2 mols O

mole ratio of O to X = 4

Simplest formula = XO₄ (answer D)