NCERT solutions for class 8 science

1. Pollution of Air and Water for High School Science Pollution is an introduction of harmful substances or contaminants into the natural environment. It can be in any form such as chemical, noise, air, heat or light etc. There are various forms of pollution in nature that are causing adverse effects in the environment. The major form of pollution to be discussed here is air and water. All humans need clean water and fresh air to survive in this world. It is an urgent need to understand and spread awareness on the importance of air and water. This is a very important chapter in science for 8th standard students of CBSE Board. Solutions to all the questions in this chapter can be easily found in any good solution key that provides NCERT Solutions for Class 8 Science. We are aware that the water and air used to be in ancient times is not the same now. It is getting highly contaminated due to anthropogenic activities. Not only humans, even plants and animals are getting affected by the pollution in air and water. Every student needs to be taught in the early days of schools on pollution and how to prevent and conserve them. Lets us have a brief understanding about the two types of pollution i.e air and water. Air pollution Every individual cannot live for a second without breathing air. It is a mixture of gases consisting of 78 percent nitrogen, 21 percent oxygen whereas carbon dioxide, argon, methane, ozone and water vapours are present in small quantities. What are the causes of air pollution? The substances that are causing air pollution are known as air pollutants. These pollutants are sometimes generated from forest fires, volcanic eruptions and also by human activities. The air pollution is mainly due to smoke coming from industries, automobiles, firewood etc. The different types of toxic gases released in the air are Sulphur oxides, Nitrogen oxides, Carbon monoxides, Volatile Organic Oxides (VOCs), Chlorofluorocarbons etc. Effects of air pollution Air pollution causes significant risk factors to human health. And also affects the other living creatures in the environment. It can even cause diseases, allergies related to respiratory problems,

2. heart diseases and lung cancer. It also has a huge effect on the growth and development of a country in terms of health, economy, agricultural and environmental productivity. Water Pollution Water is the most important natural resource. The water bodies are lakes, rivers, oceans and groundwater. All the living things require water for their survival. No one can survive without water as it is used for drinking, cooking, washing, agriculture etc. The harmful substances or contamination in water bodies are known as water pollutants. What are the causes of water pollution? Water basically gets contaminated due to harmful substances such as sewage, toxic chemicals released in the water bodies. Then it is used by humans in the form of drinking water, cleaning purposes, irrigation etc. The animals and plants are also dependent on water for their growth and development. Effects of water pollution Millions of people depend on water for their daily needs and livelihood. Many industries discharge harmful chemicals into the water bodies. This causes contamination of water. The chemicals released such as arsenic, lead, fluorides are toxic to plants and animals. The contaminated water cannot be used for drinking or agricultural purposes. This water may consist of bacteria,viruses, fungi and parasites that can cause diseases such as cholera, typhoid, jaundice. What can be done to prevent air and water pollution? ●The quality of air should be regularly monitored by government ●Create awareness among the people through workshops, lectures, campaigns etc ●Use of alternative fuels instead of fossil fuels for solar, hydropower and wind energy ●Plant more trees for fresh air in the environment ●Laws should be implemented by the industries for not disposing of toxic water directly to the rivers and lakes. ●Water treatment plants should be installed in every industry. ●Do not waste a single drop of water.

3. ●Every individual should follow REDUCE, REUSE AND RECYCLE. ===================================================================== Summary Pollution of Air and Water is a very important chapter in Science for 8th standard students of CBSE Board in India. This article gives an overview of pollution and its types such as air and water. About the Author Anu V is Senior Content Writer specializing in content writing related to education and research background. She holds an MSc degree from reputed University. Currently working on educational content for Embibe, a leading EdTech company based in India.