Question

passage 9104
directions: the solubility curves for typical common salts is shown in the graph. use the graph to answer any questions that follow.
a kno₃ solution has saturation when 75 g of salt have dissolved in solution?
a. 15°c
b. 25°c
c. 45°c
d. 55°c

Explanation:

Step1: Identify the solute and graph

The solute is \(KNO_3\), so we look at the dashed line (representing \(KNO_3\)) on the solubility graph.

Step2: Find solubility of 75g \(KNO_3\)

We need to find the temperature where the solubility of \(KNO_3\) is 75 g per 100 g of water. Looking at the graph, the dashed line ( \(KNO_3\)) at 55°C has a solubility around 75 g/100g water. At 45°C, \(KNO_3\) solubility is less than 75, at 25°C much less, at 15°C even less. So the temperature where 75g \(KNO_3\) dissolves (solution is saturated) is around 55°C.

Answer:

D. 55°C