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