Question

A metal, M, forms an oxide having the formula M2O3 containing 52.92% metal by mass. Determine the atomic weight in g/mole of the metal (M). Please provide your answer in 2 decimal places.

Answer 1

26.98g/mol

Step-by-step explanation:

The molar mass of M2O3 = 2M + 3O = 2M +(3x16) = 2M + 48

From the question, we were told that the mass percentage of M is 52.92%. This can be expressed below:

Mass of M/MM of oxide = 52.92%

2M / 2M + 48 = 52.92/ 100

Cross multiply to express in linear form

2M x 100 = 52.92(2M + 48)

200M = 105.84M + 2540.16

Collect like terms

200M — 105.84M = 2540.16

94.16M = 2540.16

Divide both side by 94.16, we have:

M = 2540.16 / 94.16

M = 26.98

The atomic weight of M is 26.98g/mol