Determine the percent composition of all elements in enstatite, MgSiO3, a mineral found in Earth's crust.

Magnesium:

Mg molar mass: 24.3050

You have one atom of Mg so, 24.211% (mass percent)

Silicon:

Si molar mass: 28.0855

You have one atom of Si so, 27.977% (mass percent)

Oxygen:

O molar mass: 15.9994

You have three atoms so, 47.812% (mass percent)