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Yes, there is water pollution. Sewage water should not be mixed with drinking water. Water purifier should be used before drinking water.

Environment chemistry deals with study of the origin, transport, reactions, effects and fates of chemical species in the environment. Mankind is faced with several types of pollution such as air pollution, water pollution, soil pollution, thermal pollution, noise pollution, metals pollution etc. It is most essential to control various types of pollution so as to save mankind and living organisms.

Chemistry and chemical process involving the minimum use and generation of harmful substances is called green chemistry Ex:‐ Earlier tetrachloroethene themes was used as solvents for dry cleaning. This compound is carcinogenic; therefore it has been replaced by liquefied CO₂ along with a suitable detergent which is less harmful.

The compounds of lead, mercury, Cd, Ni, Co, Zn etc which are the products of chemical reactions, carried in the industrial units, pollute water to a large extent and are responsible for many disease. Mercury leads to minimarts disease, lead poisoning leads to many deformities. In addition, these substances adds to the soil and harmfully affect the plant growth and the whole soil biotic system. Both ground water and water bodies are polluted due to chemical reactions known as leaching.

The smaller particulate pollutants are more likely to penetrate into the lungs. These five particles are carcinogens Inhalation of small particles irritates the lung and exposure to such particles for long period of time causes fibrosis of the lung lining. These type of disease is termed as pneumoconiosis.

It is a production process that aims at using the existing knowledge and principles of chemistry for developing and implanting chemical products and processes to reduce the use and generation of substances hazardous to the environment. The release of different harmful chemicals (particulates, gases, organic and inorganic wastes) causes environmental pollution. In green chemistry, the reactants to be used in chemical reactions are chosen in such way that the yield of the end products is up to 100%. This prevents or limits chemical pollutants from being introduced in to the environment For example, through the efforts of green chemists, H₂O₂ has replaced tetrachloro methane and chlorine gas in drying and bleaching of paper. CO₂ has replaced CFCs as blowing agents in manufacture of polystyrene foam sheet.

Earth is called a blue planet.

When pH of rain water becomes as low as 2 to 3.5. It forms acid rain.

Ozone is present in Stratosphere layer of the atmosphere.

The acids present in the acid rain are

H₂SO₄, HNO₃ and HCl.

Photochemical smog is formed as a result of photochemical reaction (i. e; in the presence of sunlight) between oxides of nitrogen and hydrocarbons.

Troposphere is the lowest layer of atmosphere.

It is peroxyacetyl nitrate.

PAN is Peroxy acetyl nitrate.

Peroxyacetyl nitrate (PAN) is one of the components of photo chemical smog and it is powerful eye irritant.

An example for non-biodegradable pollutant metal waste.

Acetic acid is not present in acid rain.

Pollutant is any substance which cause adverse effect on environment.

It is used to control of malaria and other insect borne diseases. After the war, DDT is used in Agriculture to control the damages caused by insects, weeds and various crop diseases However, due to adverse effects, its use has been banned India and it is non-biodegradable and carcinogenic.

Viable particulates: They are minute living organisms that are dispersed in the atmosphere including bacteria,fungi, moulds, algae etc. 

Non-viable particulates: They are formed by the break down of larger materials or by the condensation of minute particles and droplets.

The acids commonly present in acid rain are nitric acid, sulphuric acid and carbonic acid. Nitric acid is formed by oxidation of nitric oxide present in air to NO₂ & NO₃, which dissolve in water also present in air. Sulphuric acid is formed by the oxidation of SO₂ result in air to SO₃ followed by dissolution in water. CO₂ present in the acid dissolves in water to give carbonic acid.

Acid rain contains acids such as HNO₃ , H₂SO₄ and H₂CO₃ (along with small amount of HCl).

HNO₃ is formed by the oxidation of NO present in air to NO₂ and NO₃ and subsequent dissolution in water. H₂SO₄ is formed by the oxidation of SO₂ present in air to SO₃ and subsequent dissolution in water.

H₂CO₃ is formed by the dissolution of CO₂ of the air in water.

Viable particulates: They are minute living organisms that are dispersed in the atmosphere including bacteria, fungi, moulds, algae etc.

No-viable particulates: They are formed by the breakdown of larger material of by the condensation of minute particles and droplets.

Acid rain contains acids such as HNO₃, H₂SO₄ and H₂CO₃ (along with small amount of HCl). HNO₃ is formed by the oxidation of NO present in air to NO₂ and NO₃ and subsequent dissolution in water. H₂SO₄ is formed by the oxidation of SO₂ present in air to SO₃ and subsequent dissolution in water, H₂CO₃ is formed by the dissolution of CO₂ of the air in water.

H₂SO₄,HNO₃ and HCl.

Carbon monoxide(CO), sulphur dioxide(SO₂) and oxides of nitrogen(NO₂). 

Sun is a source of energy which does not create pollution.

Acid rain is the rain water mixed with small amount of sulphuric acid, nitric acid along with hydrochloric acid which are formed from the oxides of sulphur and nitrogen present in air as pollutants. It has a pH of 4-5.

Harmful effects of acid rain: 

(i) It is toxic to vegetation and aquatic life. 

(ii) It damages buildings and statues.

When rain falls through polluted air, it comes across chemicals such as gaseous oxides of sulphur, oxides of nitrogen, mists, of hydrochloric acid and phospheric acid etc., pH lowers down from 5.6 to 3.5 sometimes it becomes as low as 2.

The amount of dissolved oxygen present in water is limited. The abundance of phytoplankton causes depletion of this dissolved oxygen. This is because phytoplankton’s are degraded by bacteria present in water. For their decomposition, they require a large amount of oxygen. Hence, they consume the oxygen dissolved in water. As a result, the BOD level of water drops below 6ppm, inhibiting the growth of fish and causing excessive fish kill.

CFC’S (chlorofluorocarbons) that are released in the atmosphere mix with the other atmospheric gases and when eventually reach the stratosphere, gets broken down by UV radiations as fallows

CF₂Cl₂ ‐‐‐ UV rays‐‐‐ > Cl^. + CF₂Cl^.

The chlorine radical reacts with ozone and breaks down ozone molecule as follows

Cl^. + O₃ ‐‐‐‐‐ > ClO^. + O₂

ClO^. radical further reacts with atomic oxygen and produces more chlorine radicals as follows

ClO^. + O ‐‐‐‐‐‐ > Cl^. + O₂

1. It causes respiratory diseases e.g. Asthama bronchitis in human beings.

2. It causes irritation to the eyes, resulting in tears and redness. 

1. Damage the leaves of plants and retard the rate of photosynthesis. 

2. Nitrogen dioxide is a lung irritant that can lead to an acute respiratory disease in children.

1. Damage the leaves of plants and retard the rate of photosynthesis.

2. Nitrogen dioxide is a lung irritant that can lead to an acute respiratory disease in children.

Ozone layer acts as a protective umbrella and does not allow the harmful UV radiations to reach the earth's surface. If ozone is completely removed from the stratosphere, the UV radiations will fall directly on the humans causing skin cancer and on the plants affecting plant proteins.

1. Air pollutants exists in two major forms namely: 

(a) Gaseous air pollutants 

(b) Particulates

2. Gaseous air pollutants: 

Oxides of sulphur, oxides of nitrogen, oxides of carbon and hydrocarbons are the gaseous air pollutants.

3. Particulate pollutants: 

Particulate pollutants are small solid particles and liquid droplets suspended in air. 

Exarnple: 

dust, pollen, smoke, soot, aerosols.

• Smog is a combination of smoke and fog which form droplets that remains suspended in the air. 
• Smog is a chemical mixture of gases that forms a brownish yellow haze. It mainly consists of ground level ozone, oxides of nitrogen, volatile organic compounds, SO₂, acidic aerosols and some other gases.

The pollutants are slowly degradable by natural processes & remain in the environment in an unchanged form.

Ex: DDT, Some polymers, heavy metals etc. 

• At high altitudes in the atmosphere consists of a layer of ozone (O₂) which acts as an umbrella for harmful UV radiations. Ozone is considered to be earth’s protective umbrella. 
• It protects us from harmful effects of UVradiations of the sun such as skin cancer. 
• Ozone layer prevent the UV radiations to reach the earth surface. So it acts as an umbrella for the Earth.

• The pollutants which can be easily decomposed by the natural biological processes are called biodegradable pollutants. For example plant wastes, animal wastes.
• The pollutants which cannot be decomposed by the natural biological processes are called nonbiodegradable pollutants. For example, metal wastes such as Hg and Pb, D.D.T. plastics, nuclear vastcs.

Biodegradable pollutants are those which can be decomposed by bacteria. For example, dust particles, sewage, cow dung etc. Non-biodegradable pollutants are those which cannot be decomposed by bacteria. For example, plastic materials, mercury, aluminium, DDT, etc.

The main constituent of layer responsible for global warming is CO₂

In water, the source of oxygen is either atmospheric oxygen or photosynthesis carried in plants during day light. 

IR radiations

CO is not a green house gas.

It is the phenomenon where earth‟s atmosphere traps the heat from the sun & prevents it from escaping into the outer space.

Ex: CO₂, CH₄, O₃ etc 

(i) The gases which absorb solar energy near the earth’s surface and then radiate it back to the earth are called greenhouse gases.

(b) London smog : SO₂ , SO₂ and humidity

(b) Ozone, PAN and NO₂ 

CO₂ is formed by incomplete combustion of coal.