Question

Mention the effects of heat on a substance.

Answer 1

Hint: You think of all possible effects that can be caused as the result of application of heat on a body. This can be done by recalling all the concepts that we learnt related to this topic. Remember that by applying heat, we are actually increasing the thermal energy, so you could think of what could be the possible result of that.

Complete answer:
In the question, we are asked to find the effects of heat on a substance.
One of the effects of heat on a substance is that on applying heat the body undergoes expansion. This happens because, on applying heat on a body, the particles present in the body gain energy as the result of which they start to vibrate vigorously about their mean position and thereby force the neighboring particles apart. Net result of this whole process is that the body will get expanded. The order of expansion in different states of matter is given by gases>liquids>solids.
Next effect of application of heat on a body is the increase in temperature. As temperature is the manifestation of thermal energy we know that on applying heat on a body energy transfer occurs from hotter body to colder body resulting in greater thermal energy and hence, greater temperature.
Third possible effect of the application of heat on a body is the change of state. Sometimes when applying heat on a body, the temperature will remain the same but the state or phase of the body changes, that is, the solid becomes liquid and liquid becomes gas.

Note:
For the third effect, that is the change of state of substances, the increase in thermal energy on application of heat results in molecules being further apart from each other. Thereby, intermolecular attraction is reduced and thus solid changes liquid with less intermolecular attraction and liquid changes to gas which has lesser intermolecular attraction in comparison to liquid.