Question

Calculate number of atoms present 10g of oxygen in CaCo₃

Answer 1

Mol. wt. of CaCO3 = 40 + 12 + 3 X 16=100g

100 g of CaCO contains = 3 x 6.022 x 10^23 atoms of oxygen


There fore, 10 g CaCO3 will contain = 3 X 6.022 X 10^23 X 10/100 = 1.806 X 10^23 atoms of oxygen