How many moles of magnesium phosphate, `Mg_(3)(PO_(4)_(2)` will contain 0.25 mole of oxygen atoms?

Options

A. `1.25xx10^(-2)`
B. `2.5xx10^(-2)`
C. `0.02`
D. `3.125xx10^(-2)`

Answer

D

Explanation

1 mole of `Mg_(3)(PO_(4))_(2)` contains 8 mole of oxygen atom
`:.` 8 mole oxygen atoms are contained in 1 mole of `Mg_(3)(PO_(4))_(2)` and 0.25 moles of oxygen atoms are contained in `(1)/(8)xx0.25=3.125xx10^(-2)` moles of `Mg_(3)(PO_(4))_(2)`.