THE LANGUAGE OF CHEMISTRY
Introduction
The abbreviation is used in every field of study to save space, time and labor. Similarly, in chemistry, abbreviation are used to represent the name of elements, compounds and to represent reactions.
When one or more substances (elements or compounds) undergo a chemical change with the absorption or evolution of energy to give new substances (called products) this is called a change of a chemical reaction.
WATER
Water occurs in the free as well as combined state.
Next to air, water is one of the most common substances on the earth's surface. Nearly 80% of earth's surface is covered with water, it occurs in the free as well as combined state. In the free state it occurs in all the three states of matter, example - ice, liquid water and water vapor also called Solid, liquid and gas. In the combined state, it occurs as water of crystallization in hydrated salts. It takes part in almost all the chemical processes occurring in nature. Water found in the nature is called natural water, while the water obtained after some treatment is called treated water. Water plays an important role in many natural processes. It is necessary for plant and animal life. Water is essential for industries, it is also used for transportation, power generation etc.
Importance of Water
1- water is essential for the growth of plants and animals.
2- the living beings need water for almost every function which is being carried out by every cell.
3- water is needed to grow and cook food.
4- the bulk of transportation of goods to other countries is carried out through seawater.
5- water is used as a coolant in nuclear reactors.
6- water is used to generate electricity, example - hydroelectric as well as thermoelectric stations use large amount of water.
Water cycle in nature
The circulation of water from the earth's surface to the atmosphere and back to the earth is called water cycle in nature.
Physical properties of water
1- Color: pure water is colorless, transparent and clear liquid.
2- Odor : Pure water is odorless.
3- Taste: Pure water is tasteless or has a flat taste.
4- Boiling point: Pure water boils at 100 °C at one atmospheric pressure, boiling point gets affected by pressure and impurities.
5- Freezing point: Freezing point of pure water is 0 °C at 1 atmospheric pressure, just like boiling point, freezing point also gets affected by pressure and impurities.
6- Density: Water has a maximum density of 1g/cc at 4 °C, Ice has lower density than water and floats over water.
7- Specific heat capacity: specific heat capacity of water is 4.2 J/g or 1 cal/g at 15 °C, It is highest among all substances.
8- Specific latent heat of fusion of ice is, 2268 J/g or 540 cal/g.
9- Specific latent heat of vaporization of water is 336 J/g or 80 cal/g.
10- Conductivity: Pure water is a bad conductor of heat and electricity.
11- Dielectric constant: water has a high dielectric constant of 80.
Crystals
The homogenous solids having definite geometric shape, smooth plane surfaces, meeting at sharp edges are known as crystals
Water shows anomalous behavior, due to which, the life under water remains preserved
You must be logged in to post a comment.