Question

Calculate the molecular mass of NaNO3, Na2 CO3 and CaCl2 if (Ca = 40u, Cl = 35u, Na = 23u, O = 16u, N = 14u C = 12u)

Answer 1

Answer:

CaCO

3

→CaO+CO

2

The molar masses of CaCO

3

and CaO

are 100 and 56 g/mol respectively.

100 g of CaCO

3

will give 56 g of CaO

0.959 g CaO corresponds to

56

0.959×100

=1.72 g of CaCO

3

The molar mass of CaCl

2

is 111 g/mol.

1.72 g of CaCO

3

corresponds to

100

1.72×111

=1.9 g of

CaCl

2

The percent of CaCl

2

in sample is

4.22

1.9×100

=45.00 %