Question

A solid mixture consists of 27.2 g of KNO3 (potassium nitrate) and 4.8 g of K2SO4 (potassium sulfate). The mixture is added to 130. g of water. If the solution described in the introduction is cooled to 0 ∘C, what mass of KNO3 should crystallize? Enter your answer numerically in grams.

Answer 1

A solid mixture consists of 44.2g of KNO3 (potassium nitrate) and 7.8g of K2SO4 (potassium sulfate). The mixture is added to 130. g of water.

If the solution described in the introduction is cooled to 0 ∘C, what mass of KNO3 should crystallize?

(Assume KNO3 has a solubility of 14 g solute/ 100 g water)

X g of KNO3/ 130 g water= 14 g of KNO3/ 100 g water

X= 18.2 g (this is the amount of solute that dissolves at 0 degrees C in 130 g water)

if you have 44.3g of KNO3 in 130 g of water at 0 degrees celsius and only 18.2 can dissolve then

44.2g - 18.2g = 26 g left undisolved which gives you the amount that would crystallize