Give reasons:

Water is used in room coolers and hot water bags.

Water needs a large amount of heat to become hot and takes a long time to lose heat, so it neither heats up nor cools down quickly. Hence, it can absorb a lot of heat from its surroundings without becoming very hot, making it an excellent cooling agent. Therefore, water is used in room coolers to absorb heat from air and in hot water bags because it stays warm for a longer time.