Ncert- science – class 7- Chapter 13 – Wastewater Story 1 Welcome to your Ncert- science – class 7- Chapter 13 – Wastewater Story 1 1. Filtration plants uses _____ filters to remo sand steel paper none of these None 2. The direct discharge of pollutants into water bodies leads to Soil pollution All of the above Air pollution Water pollution None 3. Which of the following is wastewater? Water flowing in a river. Water coming out of a laundry. Water trickling from a damaged tap. Water coming out of a shower. None 4. The system of a network of pipes used for taking away wastewater from homes or public buildings to the treatment plant is known as sewerage transport system. sewers treatment plant. None 5. Which of the following is/are products of wastewater treatment? Biogas Aerator Both biogas and sludge Sludge None 6. Open drain system is a breeding place for which of the following? All of these Flies Mosquitoes Organisms which cause diseases None 7. Pick from the following one chemical used to disinfect water Washing soda Coal Chlorine Silica None 8. Polythene and plastics Degrade in the environment very easily Are non-biodegradable and very harmful Do not generate any bad odour Are not harmful None 9. Which of the following is biodegradable? Aluminium foil Aluminium Orange peels Plastic bottle None 10. Biodegradable waste Does not decompose Decomposes in nature by microbes Enters the food chains then causes bio magnification Accumulates in environment None 11. Which of the following is a part of inorganic impurities of the sewage? Pesticides Phosphates Urea Vegetable waste None 12. Bacteria that decompose organic wastes are called Anaerobic bacteria Aerobic bacteria All of these Lactobacillus bacteria None 13. Bacteria that decompose organic wastes are called Anaerobic bacteria Aerobic bacteria All of these Lactobacillus bacteria None 14. Which among the following are ways to conserve water? Turn off the taps while brushing teeth. All of the above Boil limited cups of water for drinking. Use less/limited water while bathing. None 15. In a filtration plant water is filtered using layers of clay and fine gravel. sand and fine gravel. sand and clay. sand, fine gravel and medium gravel. None 16. An example of source reduction of waste is Burning Backyard composting Making paper aero planes Throwing things that are old None 17. Addition of harmful substance in water leads to High oxygen demand Water pollution Microbial growth Algal bloom None 18. Which of the following is removed when wastewater is passed through bar screens? Cans Grit Pebbels Sand None 19. Water polluted by various human activities causes a number of water borne diseases. Which of the following is not a water borne disease? Cholera Dysentry Typhoid Asthma None 20. Which of the following is not an example of municipal solid waste? Sewage Paper Packing materials Batteries None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
