Answer:
3grams
Explanation:
The reaction for the production of Magnesium dioxide will be
Mg + O2 → MgO
we have 5g of MgO (molar mass 40g)
no of moles of MgO = 5/40 = 0.125
Using unitary method we have
1 mole of Mg require 1 mole of MgO
0.125 Mole of MgO = 0.125mole of Mg
n = given mass /molar mass
0.125 = mass / molar mass
mass = 0.125* 24 = 3grams