Chemical and physical properties of water

Chemical and physical properties of water 

Water Chemical properties

According to Aristotle and Empedocles water is element. This consept is valid until the 18th century when it was shown that water is a compound of specified composition: one oxygen atom and two hydrogen atoms linked covalently. H2O is the chemical formula for water, which we know by heart from school. On the one side of the oxygen atom are located two hydrogen atoms. Oxygen is negatively charged, and hydrogen – positive, so the water molecules that are prepared as a result are oppositely charged and attract. This is called cohesion.

Water has the property to dissolve thousands of substances. There is no better and more perfect solvent than the water. It takes along its way and carries any harmful or useful chemical compounds. However, if we talk about clean water, it has a neutral pH of about 7 and it is not acidic and not alkaline.

Physical properties

Water is a unique substance in their physical behaviour. It is a liquid with no taste and smell under normal pressure and temperature. This stuff is the one that can be in all three aggregate states: liquid, solid and gaseous. In its normal liquid form, it has a slight bluish tint. Gaseous state of water – water vapor – is invisible. The ice has not color. As a conclusion regarding the color, water is colorless. In fact, sunlight reaches the Earth surface and underwater, thanks to this property of water. Otherwise there would be no life in darkness, which would have been, if the water was colored.

Water moves, enter into relations with other substances, changes in one or another state, but never vanishes. It freezes at 0°C and boils at 100°C at sea level. Interesting fact about scientists is that the solid state of water – the ice – is less dense than the liquid phase. For this reason, the ice floats on water surface without sinking. Water in freezing expands. There are no other substances with similar properties.

Another specific characteristic of water is its high heat index, which makes it indispensable in industry and households as a cooler or heater. Thanks to the high heat index is the gradual change of seasons – a gradual cooling or warming the air, which depend on ocean temperatures.

Water is a conductor if there are ions dissolved in it. Otherwise it is not a conductor. Water is cohesive and adhesive, i.e. creates surface tension and gravity. Water molecules attract each other and droplets are formed.

Water cycle

As mentioned, water quantity of the planet is always the same, only the state, in which it is, changes. Different parts of the hydrosphere and atmosphere contain various concentration of water, which makes periodic transitions from one state to another according to the hydrological cycle, called cycle of water: it evaporate – from aquatic basins and plants – in the air. There, in the clouds, water vapor is concentrated and cooled, then return to earth as rains. Rains flow into the ocean. So the circle closes.

Water is an essential substance for the existence of living nature – plants, people and animals are composed mostly of water, which maintains and purified their bodies so that they function properly. Everything is thanks to the extraordinary physical and chemical capabilities of the water.