Question

Salt is dissolved in a flask of tap water. Distilling the mixture causes the salt to separate from the water. Which type of energy is required to begin the distilling process?
A)chemical energy
D).electrical energy
C).mechanical energy (motion)
D).thermal energy

Answer 1

D.

The water must be heated and removed in distillation, so thermal energy is required.

Answer 2

The correct option is D.

Thermal energy is the energy derived from heat. To separate the mixture of salt and water, heat has to be applied to the mixture. The energy from the heat will make the molecules of the water to gain kinetic energy and to move around the container more rapidly until the inter molecular forces between the molecules are broken and they escape as steam into the atmosphere. It is only the salt particles that will be left behind after all the water has evaporated.