Question

What is the mass % of a solution if it contains 20g of salt mixed with 100 g of water? Show your work

Answer 1

You’d still have 100 gm of water. The mass of water you have hasn’t changed. However you will have 120 gm of saline solution. But the volume will have changed. Oddly and counterintuitively when sodium chloride dissolves in water to make a saturated solution there is a 2.5 per cent reduction in volume.

Answer 2

Explanation:

The mass of the solution will contain all ten grams of salt up to the point that the water is completely evaporated and you have ten grams of salt left over. Salt is not volatile at normal temperatures.