Question

Calculate the number of atoms in 12g of MgO

Answer 1

Weight of one mole of MgO =27+16 =43 gms. So 43 gms has 6.022×10^23 molecules of MgO . hence 12 gms has 6.022×10^23(12/43)= 0.279(6.022)×10^23 =1.680138×10^23 molecules= 3.360276×10^23 Atoms .