How many moles of magnesium phosphate Mg_3 (PO_4)_2 will contain 0.25 mole of oxygen atoms ?

How many moles of magnesium phosphate Mg_3 (PO_4)_2 will contain 0.25

1.	How many moles of magnesium phosphate Mg_3 (PO_4)_2 will contain 0.25 mole of oxygen atoms ?
Answer» (a) `0.02` (b) `3.125 xx 10^(-2)` (C) `1.25 xx 10^(-2)` (d) `2.5 xx 10^(-2)` Solution :From the formula, `Mg_3(PO_4)_2`, it .s clear that 8 moles of oxygen atoms are present in 1 mole of MAGNESIUM phosphate. `therefore` 0.25 moles of oxygen atoms will be present in`1/8 xx 0.25 = 3.125 xx 10^(-2)` moles of `Mg_(3)(PO_(4))_(2)`.