CHEMISTRY [3 Mark Question Answer]

A combination of oxides of nitrogen and sulphur, partially oxidised hydrocarbons and their derivatives produced by industries and automobiles form dark, thick dust and soot-laden fog known as smog.
Damaging effect: Smog is noxious and irritating. It reduces visibility, induces respiratory troubles and can cause death by suffocation.
Photochemical smog: Damages the tissues of certain plants and even decreases the yield of citrus fruits and grapes.

Causes:
Sulphur and nitrogen oxides are emitted by burning fossil fuels. Such smoke and gases entering the atmosphere make a dilute soup of sulphuric and nitric acids. This falls on the land surface in the form of acid rain damaging the things on Earth.
Impacts:

1. Acid rain accelerates the decay of building materials and paints, including buildings, statues, and sculptures which are part of our nation's culture and heritage.
2. Acid rain causes respiratory problems in humans, especially for people suffering from asthma. It may cause throat irritation, dry cough, and severe headache.

Ways of reducing the presence of greenhouse gases:

• Minimize the use of automobiles: Depending on the situation, one can use a bicycle, the public transport system, and carpools.
• Plant more trees to increase green cover.
• Avoid burning of dry leaves and wood.
• Avoid smoking. It is illegal to smoke in public places and workplaces because smoke is harmful not only for the one who is smoking but also for others sitting nearby.
• Help people in understanding global warming; most people are unaware of it.

A scrubber can also be used to reduce the formation of acid rain. It is a device that absorbs gaseous pollutants. It is used for removing sulphur dioxide from a smokestack and usually consists of a fine spray of water and gas rising from the stack, which is passed through the scrubber where water absorbs sulphur dioxide.

It is a highly poisonous gas.
When inhaled, it passes through the lungs directly into the bloodstream. There it combines with haemoglobin, the substance which carries oxygen to body tissues. Because haemoglobin binds with carbon monoxide 200 times more strongly than oxygen, even low concentrations of carbon monoxide in the air have magnified effects on the body.
It reduces the oxygen-carrying capacity of blood by an amount equivalent to the amount of haemoglobin converted to carboxyhaemoglobin.
Haemoglobin + CO → Carboxyhaemoglobin