How can I calculate solubility of potassium nitrate?

1 Answer
Jul 28, 2014

Answer:

The only way to determine the solubility of potassium nitrate is to do an experiment or interpolate from a solubility graph.

Explanation:

Solubility is the mass of a solute that can be dissolved in a given mass of solvent.

Solubility varies according to temperature for the same solute and solvent.

The solubility graph for potassium nitrate in water is shown below.

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EXAMPLE

What is the solubility of potassium nitrate at 50 °C?

Solution

Read along the horizontal axis until you reach 50 °C. From there, extend a line upwards until it meets the graph.

Then extend a horizontal line to the vertical axis. Read the temperature at that point.

The solubility is about 90 g of KNO₃ per 100 g of water.