solubility chemistry

Question

A mass of 5 g of potassium chlorate is dissolved in 10 mL of water at 95°C. As the solution is cooled, at what temperature will a precipitate first appear?

Answer 1

As was the case with your previous question on solubility, you will need to have a solubility curve. The curve I found on the internet has solubility in g / 100 mls

You have 5 g KClO₃ / 10 ml H₂O which is equal to 50 g KClO₃ / 100 mls. The temperature is 95ºC and the curve shows it is soluble at this temperature. As you follow the curve down to lower temperature, you want to find the point (temperature) where the solubility is LESS THAN 50 g / 100 mls. On the curve that I am using, that occurs at around 89º-90ºC, so that is the temperature at which a precipitate will form.