Question

What is the weight of 1 mole of the following
(i) NaCl
(ii) CaCO₃

Answer 1

(i) Molecular mass of NaCl: 23 amu + 35.5 amu = 58.5 amu
Molar of mass : NaCl: 58.5 g/mol
No. of Moles = Mass / Molar mass
Mass = 1 × 58.5g
Therefore, mass of 1 mole of NaCl is 58.5 g.

(ii) Molecular mass of CaCO₃ = (1 × Ga + 1 × C + 3 × O)
= (1 × 40 + 1 ×12 + 3 × 16)
= 40 + 12 + 48 = 100
Molar mass of CaCO₃ = 100 g
Nor of Moles = Mass / Molar mass
Mass = 1 × 100 = 100 g
Therefore, mass of 1 mole of CaCO₃ is 100 g.