Water is a naturally occurring substance that occurs freely in our environment. The most distinguishing feature is the ability to retain heat over prolonged periods of time than most other naturally occurring substances. Every substance, be it air, water, or minerals, has a particular heat capacity which is the amount of heat it can absorb for it to be raised by one degree Celsius. A substance’s heat capacity is determined by its chemical composition, and water, besides it being a liquid, has the highest heat retention above all others.
Each compound has its heat specificity: the quantity of heat needed to raise one gram of a substance by one degree Celsius. Water having a higher heat specificity translates to it requiring an enormous amount of energy for there to be a temperature change. When heating both a piece of iron and water, you will notice that iron will take a shorter time before it’s fully heated. Iron unlike water is a positive molecule with free-floating electrons around its atom that makes it a good conductor of heat.
This is attributed to its minimal amount of heat specificity making iron one of the best conductors of heat. Comparatively, water uses a significant amount of time before its boiling point is reached, or when a significant change of temperature is recorded. The comparison waylays that water is a poor conductor of heat as compared to iron, dictated by the movements of their electrons.
The structure of water’s molecule comprises hydrogen and oxygen atoms, with one molecule of oxygen sandwiched by two hydrogen atoms. This results in an unbalanced compound with a slightly negative charge brought by extra electrons from the oxygen atom. Like charges repel each other while unlike charges attract, resulting to water weaker hydrogen bond that keeps on breaking and forming. Because of this chemical structure, water conforms to being a liquid, which then requires a lot of energy for it to be raised by a degree.
If you ever notice while walking on a beach in the summer, the sand heats up faster than water, and may sometimes require treading on the water to cool off your feet. Sand, on having a lower heat capacity than water, takes up heat quickly, and its temperature quickly raised whenever its heat capacity threshold is reached. Having smaller heat retention equals getting heated up quickly, but those with high capacity take some time. The heat specificity of water per gram is 4.186 joules meaning water consumes that volume of energy to raise one gram of water by one degree Celsius.
The reason why water takes a considerable length of time to boil is that heat is quickly spent on breaking the bonds first before heating commences. Breaking bonds of liquid requires a decent amount of heat as compared to solid elements because of the unstable nature of the liquid. They tend to “evade” heat by swirling around in a cycle, making them a poor conductor of heat. Besides, the fluidity of water itself makes it harder for the uniform distribution of heat.
Assuming the source of heat is from a single source direction, then the first cold layer will be heated first, gets lighter, then give way to a denser cold-water layer. This will then repeat several times before the layers are uniformly heated. The characteristics that make water take a long time to heat also make water a good retainer of heat. After the temperature of the water has been raised significantly, it takes time to disperse the same energy off its electrons. A practical example of this is when swimmers feel colder outside water in the evenings just as the sun is going down.
The heat retention of water has enabled it to hold heat for longer periods by making it harder for water to quickly warm up and disperse heat too. This feature has made water a perfect medium upon which marine life comfortably lives. If water had so much temperature change, then it would have been harder for fish to keep adjusting for the right temperatures. Water in the oceans absorbs most of the heat from the sun that plays a big role in moderating the climate around coastal areas. The causative of water holding heat for a longer period is its high heat retention, which makes water take up a lot of energy, before being raised by one degree Celsius.