Question

What is the total mass of KNO3 that must be dissolved in 50. grams of H2O at 60.°C to make a saturated solution?

(1) 32 g (3) 64 g
(2) 53 g (4) 106 g

Answer 1

at 60ºC:

106 g KNO₃ -------------- 100 g (H₂O)
? g KNO₃ ------------------ 50.0 g (H₂O)

mass KNO₃ = 50.0 * 106 / 100

mass KNO₃ = 5300 / 100

= 53 g of KNO₃

answer (2)

hope this helps!

Answer 2

53g

Step-by-step explanation:

First we plot the solubility graph for KNO3 as shown in the image attached. From the graph, we see that the solubility of KNO3 per 100g of solution is 106g.

Hence if 106g of KNO3 dissolves in 100g

Xg of KNO3 dissolves in 50g

50×106/100 = 53g of KNO3