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The microorganisms present in the soil require moisture (water) and nutrients for growth and survival. Choose from the options below the habitat (place) where the soil has plenty of water and nutrients. (a) Desert (b) Forest (c) Open field (d) Cricket ground

(b) Forest In forests, there will be a lot of trees which hold the soil and prevents soil from erosion. Humus makes the soil fertile and... View Article

Think and suggest some ways to minimise waste and pollutants at their source, taking your home as an example.

To minimize waste and pollutants at their source the following measures can be taken: We should avoid use of plastic bags by using bags made up... View Article

Describe various steps of cleaning wastewater in a wastewater treatment plant.

Wastewater is passed through bar screens. Large objects like rags, sticks, cans, plastic packets, napkins are removed. Water then goes to a grit... View Article

A very _____ number of our people defecate in the open. It may cause _ pollution and soil pollution. Both the surface water and _ water get polluted. _ water is the source for wells, tubewells and _. Thus it becomes the most common route for _ borne diseases like _____, dysentery, etc.

A very large number of our people defecate in the open. It may cause water pollution and soil pollution. Both the surface... View Article

The terms sewage, sewers and sewerage are interlinked with each other. Can you explain, how?

Wastewater released by home, industry, hospital etc. are called sewage. The small and big pipes that takes away sewage is called sewers. The... View Article

What are the different types of inorganic and organic impurities generally present in sewage?

Different types of inorganic and organic impurities generally present in sewage are as follows: Inorganic impurities: nitrate, phosphate, metals... View Article

A mixture (x) in water contains suspended solids, organic impurities, inorganic impurities (a), nutrients (b), disease-causing bacteria and other microbes. Give names for (x), (a) and (b)?

Sewage is actually the wastewater that is released from houses, hospitals, industries, offices and other sources. It also includes the rainwater... View Article

Three statements are provided here which define the terms – (a) sludge (b) sewage and (c) wastewater. Pick out the correct definition for each of these terms. (a) The settled solids that are removed in wastewater treatment with a scraper. (b) Water from the kitchen used for washing dishes. (c) Wastewater released from homes, industries, hospitals and other public buildings.

a) The settled solids that are removed in wastewater treatment with a scraper. Sludge - It is the collection of settled solids that are removed... View Article

Given below is a jumbled sequence of the processes involved in a wastewater treatment plant. Arrange them in their correct sequence. (a) Sludge is scraped out and skimmer removes the floating grease. (b) Water is made to settle in a large tank with a slope in the middle. (c) Large objects like plastic bags are removed by passing wastewater through bar screens. (d) Sand, grit and pebbles are made to settle by decreasing the speed of incoming wastewater. (e) Wastewater enters a grit and sand removal tank.

The major aim of wastewater treatment is to remove as much of the suspended solids as possible before the remaining water, called effluent, is... View Article

Why should we not throw (a) used tea leaves into the sink? (b) cooking oil and fats down the drain?

a) We should not throw used tea leaves into sink as it chokes the drain and do not allow free flow of oxygen which hampers the degradation... View Article

A man travelling in a train threw an empty packet of food on the platform. Do you think this is a proper waste disposal method? Elaborate.

This is not a proper waste disposal method. We should throw the empty packets into proper dustbins. Generally, these empty food packets are made... View Article

Name two alternative arrangements for sewage disposal where there is no sewerage system.

Two alternative arrangements for sewage disposal where there is no sewerage system- The low cost on-site sanitation systems can be adopted like... View Article

Animal waste, oil and urea are some of the organic impurities present in sewage. Name two more organic impurities present in sewage.

There are both organic and inorganic impurities present in the sewage. Organic impurities present in sewage are- (I). Vegetable and fruit peel... View Article

Name two inorganic impurities present in sewage.

Two inorganic impurities present in sewage are nitrates and phosphates. Sewage is the wastewater released by hospitals, homes or industrial... View Article

How are open drains harmful to human health?

An open-drain is mostly used to collect wastewater that is not sewage. Use of open drains to dispose of sanitary waste is extremely unhygienic... View Article

State whether the following statement is True or False. In case a statement is false, write the correct statement.Where underground sewerage systems and refuse disposal systems are not available, the high-cost on-site sanitation system can be adopted.

False The low cost on-site sanitation systems can be adopted when the underground sewerage systems and refuse disposal system are... View Article

State whether the following statement is True or False. In case a statement is false, write the correct statement.Wastewater could be reused.

True Wastewater can be treated using wastewater treatment plant and used for drinking, washing, etc. again. Use the water filtered out by ROs... View Article

State whether the following statement is True or False. In case a statement is false, write the correct statement. Used water is wastewater.

True Water that has been used once is considered as waste water. Water is used for almost every activity. This water gets dirty during... View Article

State whether the following statement is True or False. In case a statement is false, write the correct statement. (a) Sewage is a solid waste which causes water pollution and soil pollution.

False Sewage is actually the wastewater that is released from houses, hospitals, industries, offices and other sources. It also includes the... View Article

Why are open drains a concern?

Mosquitoes fly mostly breed in dirty water or areas and in open water. Open drains are dirty and have wastes in it, which makes it suitable for... View Article

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