Question

How are 0.50 mol Na₂CO₃ and 0.50 M Na₂CO₃ different?

Answer 1

Molar mass of Na₂CO₃ = (2 × 23) + 12.00 + (3 × 16) = 106 g mol^-1
Now, 1 mole of Na₂CO₃ means 106 g of Na₂CO₃.
∴ 0.5 mol of Na₂CO₃ = \(\frac {106\  g}{1 \ mole} × 0.5\  mol \) Na₂CO₃
 = 53 g Na₂CO₃
⇒ 0.50 M of Na₂CO₃ = 0.50 mol/L Na₂CO₃

Hence, 0.50 mol of Na₂CO₃ is present in 1L of water or 53 g of Na₂CO₃ is present in 1L of water.