Question

Moles of oxygen atoms in 9.00g of magnesium nitrate

Answer 1

Answer:

We know,

No. of moles =

$\frac{given \: mass}{molar \: mass}$

molar mass of Mg(NO3)2 = (1 × 24) + 2 × {(1 × 14) + (3 × 16)} = 148

Given mass = 9 g

Thus, no. of moles = 9/148 = 0.067

1 mole of magnesium nitrate contains 6 moles of oxygen atoms

0.067 moles of magnesium nitrate contains

= 6 × 0.067= 0.402 moles of oxygen atom

Thus, 9 grams of magnesium nitrate contains 0.402 number of moles of oxygen atom