Question

How many moles of magnesium phosphate, Mg₃(PO₄)₂ will contain 0.25 mole of oxygen atoms?
(A) 0.02
(B) 3.125 × 10⁻²
(C) 1.25 × 10⁻²
(D) 2.5 × 10⁻²

Answer 1

Answer:

(B) 3.125 × 10⁻²

Explanation:

Magnesium phosphate = Mg3(PO4)2 (Given)

Mole of oxygen atoms = 0.25 (Given)

Thus,

One mole of Mg3(PO4)2 consist of 8 moles of oxygen atom = 1/8

x moles of Mg3(PO4)2 consist of 0.25 moles of oxygen atom = x/0.25

Therefore,

0.25 mole of oxygen = 1/8 × 0.25

= 3.125 × 10⁻²

Therefore, magnesium phosphate will contain 3.125 × 10⁻² moles.