Today is

By: Ikedi Ani-okoye

Airsupply

We live breathe and move at the bottom of an immense ocean air called the atmosphere. Air is an invisible mixture of gases, made up of a teeming mass of millions of tiny gas molecules that move about randomly and at high speed, Without air, the Earth would be a lifeless planet, because the gases air contains are vital to plants and animals.

Fractional distillation

The gases in air have many uses. For example, divers use tanks of oxygen to enable them to breathe underwater, and nitrogen is used in explosives. Gases are extracted from air by a process called fractional distillation. Air is cooled and compressed until it forms a blue liquid. When the liquid expands and warms up, each gas boils off at a different temperature and is collected separately

Compositlon of air

Any volume of pure, dry air is 78.09% nitrogen, 20.95% oxygen, 0.93% argon, and 0.03% carbon dioxide and other gases.

Air pollution supply

Air is not naturally "pure" and contains varying amounts of other substances, such as dust, water vapour, bacteria, pollen, and polluting gases. Air pollution from industry and traffic can cause serious health problems in towns and cities, as well as long-term damage to the environment.

Smog supply

The hazy air pollution that hangs over an urban area is called smog. Sulphurous smog is the result of burning fuels with a high sulphur content, such as coal. Photochemical smog ocean when sunlight causes car exhaust fumes to react together.

Water vapour

Up to 4 per cent of the volume of air may be water vapour. Warm air can hold more water vapour than cool air. A can of cold drink absorbs heat from the air around it. As the air cools, water vapour condenses out of the air to form droplets on the outside of the can.

Air pressure

Air exerts a force on objects because its moving molecules are constanty colliding with them. Air pressure is a measure of this force. The pressure of the open air is called atmospheric pressure. It is lower at high altitudes, where the air is less dense.

Barometer

A device that measures atmospheric pressure is called a barometer. It can used to forecast a change in the weather, because air pressure varies slightly from day to day with changes in the air's temperature and humidity.

Sucking

When a person sucks on one end of a drinking straw, the lungs reduce the air pressure inside the straw. Atmospheric pressure on the liquid's surface does the rest, pushing down on the liquid, and making it rise up through the straw.

Compressed air supply

The pressure of air can be increased by compressing it - that is, pumping more more of it into a limited space. Bicycle tyres are filled with compressed air to give a smooth, comfortable ride.