Question

A researcher wants to test the solubility (property of being dissolved) of salt in water as the temperature of the water increases.
Design an experiment to test his hypothesis that as the water temperature increases the solubility of the salt in water also increases. Include the following in your experimental design: experimental setup, procedure for data collection methods and criteria for evaluating the hypothesis.
Materials: salt, water, beakers, heat source, thermometer, balance

Answer 1

The researcher may first weight the beaker with water and then start to heat the water to a constant temperature, for example 30 °C and then start adding salt and stirring. He should add salt slowly until solid salt starts to become visible and the solution starts becoming cloudy. When this happens, he should quickly weigh the beaker. The increase in mass is the mass of salt dissolved at that temperature.
The procedure is then repeated but at an increased temperature until 5-6 temperatures have been tested.