Question

How are 0.50 mol Na₂CO₃ and 0.50 M Na₂CO₃ different?

Answer 1

According to the given information, 0.5 mol of Na 2CO 3 means half of molar mass of Na 2CO 3.

Molar mass of Na 2CO 3 =  

                                               = 106 g mol-1

Its half is 53g.  

But 0.5 M of Na 2CO 3 means half mole of Na 2CO 3 dissolves in 1L solution, i.e.53g of Na 2CO 3 is present in 1L of solution.

M is the unit of molarity while mol is the unit of molecular mass.