Question

If a sodium chloride (NaCl) solution in water at 40°C has reached a concentration 50% calculate the quantity of NaCl crystals that will form once crystallization has been started in per 100 g water. The solubility of NaCl at 40°C is 36.6 g/100 g water.

Answer 1

13.4g of NaCl will crystallize per 100g of water at 40°C.

Step-by-step explanation:

Solubility stands for the maximum amount of solute that may stay dissolved per 100 g of water at a specific temperature. A solution with this concentration is known as a saturated solution. At 40°C, every 100 g of water, 36.6 g of NaCl can remain dissolved. If more solute is added to the solution the excess will crystallize and precipitate. Since prior to criystallization there are 50 g of NaCl dissolved, what will precipitate will be:

50g - 36.6g = 13.4g