Answer:
As a student when you see such type of questions first thing which should come in your mind is what is the concept hidden in question
It will help in understanding how to calculate individual elements moles
Moles of Mg(NO3)2= 4.12
Mole of “ Mg “ present in compound= 1×4.12moles
Mass of Mg = 4.12× 24
=98.88 g
Moles of “N” present in compound= 2×4.12
= 8.24moles
Mass of N = 8.24 ×14= 115.36g
Moles of”O” present in compound= 6×4.12
= 24.72 moles
Mass of oxygen present in compound= 24.72× 16
=395.52g
