In general, all substances expand on heating. For example, when the metallic cap of a bottle is so tight, it is kept in hot water, this would allow the cap to expand and loosening it to unscrew easily. In case of liquids, we can observe the expansion of mercury in a thermometer when it is put in hot water. In the cases of gases, you may have observed that a cycle tube which is fully inflated may bursts in hot summer due to expansion of air in it.