Question

solids expand on heating give reason

Answer 1

As we know, not all solids but metallic solids expand on heating, as on increasing the temperature electrons get heat energy and this heat energy gets converted to kinetic energy. Hence they move and the solid get expanded.

Answer 2

If a substance is heated its atoms and molecules vibrate faster and their kinetic energy increases. ... Due to this the atoms and molecules take up more space and causes increase in size in solids