Water

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What is Water?

Water is the most common term student study in the physical chemistry branch. Here, we have covered all the important points related to water like what is water, its properties, chemical formula, and its uses. Let’s answer the main question first what is water?? Water is the most important natural resource, more than 70% of the earth’s area is occupied by water. However, hardly 2.5% makes up the total world’s, supply of freshwater including the frozen water in the polar ice caps and glaciers.

Sources of Water

Percentage of Water

Oceans

97.33

Saline lakes and inland seas

0.008

Polar ice and glaciers

2.04

Groundwater

0.61

Lakes

0.009

Soil moisture

0.005

Atmospheric water vapour

0.001

Rivers

0.0001


What is Water in Chemical Terms?

Water is a chemical compound composed of hydrogen and oxygen. Water exists in all three states: solid, liquid, and gas. Water is a major constituent of all living things (plants, animals, and human beings) and of the atmospheric environment in which we live. 

What is Water Made of?

The most common question asked by the students is what is water made up of? When studying the solvent chapter in the physical chemistry branch one gets the idea of what is water made up of? Water is made up of two hydrogen atoms and one oxygen atom. Water occurs both in the free state and in the combined state. The IUPAC name of the water is oxidane. 

What is the Water Chemical Formula?

As we know water is made up of two atoms of hydrogen and one atom of oxygen, the chemical formula for the water is H2O. The chemical name of the water molecule is dihydrogen oxide. Water is a chemical compound made up of two elements hydrogen and oxygen combined in the ratio of 1:8 by mass.

Structure of Water Molecule

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Water molecules exist in the bent shape. The hybridisation of the water molecule is SP3. the angle between the two bond pairs is less than 180 degrees due to the repulsion between the lone pair-lone pair. 

Properties of Water

The physical and chemical properties of water depend upon the nature and strength of the bond present in the oxygen and hydrogen. The presence of lone pair affects the reactivity of water. The physical and chemical properties of water are given below:

Physical Properties of Water

  • Water naturally occurs in a liquid state at a normal temperature.

  • Water is a colourless chemical compound.

  • Water is an odourless compound.

  • Water is tasteless in nature.

  • Water is a compound that holds the ability to form supercritical fluid.

  • Water is homogeneous in nature.

  • The boiling point of the water molecule is 100 degrees celsius.

  • Water freezes at 0 degrees celsius.

Chemical Properties of Water

  • Pure water is a non-conductor of electricity.

  • The latent heat of the ice is 336 J/g.

  • The latent heat of the vapourization value of water is 2260 j/g.

  • The specific heat capacity value of the water molecules is 4.2 J

  • The dielectric constant value of the water is very high.

  • Water acts as a solvent.

  • Water is a polar inorganic molecule.

Different States of Water

Water exists in three different states. It holds the properties of forming strong hydrogen bonds. The different states of water are:

  • Solid- Ice

  • Liquid- water

  • Gas- water vapour

Importance of Water

  • Water present in natural bodies like rivers, lakes, and oceans holds the air dissolved in it. This dissolved air plays an important biological role for aquatic animals.

  • Aquatic plants make use of dissolved carbon dioxide for photosynthesis to prepare food.

  • Marine organisms extract calcium carbonate from calcium bicarbonate to build their shells.

  • Dissolved salts present in the water supply the essential nutrient needed by our bodies.

Uses of Water

  • Water is used in our daily life purposes like drinking, bathing, and cooking.

  • Generally, Water is used in all types of industry like the textile industry, paper industry, automobiles industry, etc.

  • Water is used as a solvent.

  • Water is used in all types of laboratories like microbiology lab, pharmaceuticals lab, chemical lab.

Did You Know?

  • Water is known as the universal solvent.

  • Nearly 70 % of our body weight is water.

  • The gases dissolved in the water can be easily expelled by boiling the water.

  • Distilled water and boiling water have no taste.

FAQ (Frequently Asked Questions)

Q1.: What is the Latent Heat of Vaporization of Water?

Ans. The energy required to change water into its vapour at its boiling point without any change in temperature is called the latent heat of vaporization of water. Its value is 540 cal/ g.

Q2. Is water a Combustible Substance?

Ans. No, water is not a combustible substance. The properties of water are different from those of its constituents elements, hydrogen, and oxygen.