Question

Hot water bottles are used for fomentation. This shows that water-

Answer 1

Hint: The application of warm, soft, medicinal substances for easing the pain by relaxing the skin is called fomentation. Hot water bottles are usually used in fomentation due to its ability to provide warmth for longer duration.

Complete answer:
Water does not cool due to its high specific heat capacity. This property of water is exploited through the use of hot water bottles. Also, if you notice the structure of a hot water bottle, you will realise that after water is poured inside there is no place for even the water vapour to escape. The only place for the heat to escape is through the surface of the water bottle. This complete isolation by water bottle lets it to provide warmth for even more time duration.

Additional information:
The main use of hot water bottles is in relieving the pain of body parts. Modern hot water bottles are made from silicon which resists the hot water more effectively and does not degrade as quickly as rubber bottles. Apart from medical uses, it is also used as bed warmers.

Note:
While using the hot water bottle for fomentation, do not keep it at one place of skin for a longer duration as it can cause burns in that area. Try to shift it around the place of pain after a small interval of time. Many times, people use it for drinking purposes which should be avoided at all costs. For drinking water purposes, only flask bottles should be used.