Soil pollution and pesticides

28 questions on Soil pollution and pesticides from the Environmental Chemistry chapter: 6 NEET level, 11 JEE Main, 11 JEE Advanced. Each one opens with its answer and solution.

• DDT belongs to which class of pesticides? NEET level
• Which one of the following is used as a herbicide? NEET level
• DDT accumulates in the fatty tissues of animals mainly because it is NEET level
• Organophosphate pesticides kill insects mainly by inhibiting the enzyme NEET level
• The herbicide 2,4-D is chemically NEET level
• The increase in concentration of a non-degradable pesticide such as DDT at successive trophic levels of a food chain is called NEET level
• Organophosphate insecticides replaced DDT in many applications because, compared with DDT, they JEE Main level
• Run-off of fertilisers rich in nitrate and phosphate into a pond leads to eutrophication. The final cause of oxygen depletion in the pond is JEE Main level
• Assertion (A): DDT undergoes biomagnification in food chains. Reason (R): DDT is a chlorinated organic compound. JEE Main level
• Match the pesticide in Column I with its category in Column II. Column I: P. Aldrin; Q. Sodium chlorate; R. Bordeaux mixture (copper sulfate and lime); S. Carba... JEE Main level
• Which pair of pesticides acts by inhibiting acetylcholinesterase? JEE Main level
• Repeated heavy use of ammonium sulfate fertiliser makes soil acidic. The reaction responsible is nitrification, NH4+ + 2O2 -> NO3- + 2H+ + H2O. The soil acidity... JEE Main level
• Aldrin, once applied to soil, is slowly converted by oxidation (epoxidation) into JEE Main level
• Which combination of properties makes a pesticide the greatest long-term hazard to a food chain? JEE Main level
• BHC (benzene hexachloride) is made by adding chlorine to benzene in sunlight: C6H6 + 3Cl2 -> C6H6Cl6. Its molecular formula and use are JEE Main level
• Assertion (A): Organophosphate insecticides are preferred to DDT for environmental reasons even though many are more acutely toxic to mammals. Reason (R): Organ... JEE Main level
• The number of chlorine atoms in one molecule of DDT, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane, is JEE Main level
• A white insecticide X is made by adding chlorine to benzene in sunlight, C6H6 + 3Cl2 -> C6H6Cl6. Using C 12, H 1 and Cl 35.5, the type of reaction at benzene an... JEE Advanced level
• Four pesticides were tested. Data: half-life in soil and log of octanol-water partition coefficient (a high value means strongly fat soluble). A: 4 days, 1.5; B... JEE Advanced level
• Arrange these events from fertiliser run-off in the correct order. P. Algae die and aerobic bacteria decompose them; Q. Nitrate and phosphate enter a lake; R. D... JEE Advanced level
• A field soil holds a pesticide at 64 mg per kg. Its degradation is first order with half-life 2.5 years. A safe limit of 2 mg per kg is set. After how long is t... JEE Advanced level
• Use C 12, H 1, O 16, Cl 35.5. A field receives 4.42 kg of 2,4-D (formula C8H6Cl2O3). In the soil it degrades by first order kinetics with half-life 10 days. The... JEE Advanced level
• Select the correct statements about DDT. JEE Advanced level
• Select the correct statements about organophosphate and carbamate pesticides. JEE Advanced level
• Select the correct statements about herbicides and insecticides. JEE Advanced level
• Excess fertiliser washes from farmland into a lake and into the nearby groundwater. Select the correct statements. JEE Advanced level
• Select the correct statements. JEE Advanced level
• A river contains DDT at 0.0030 ppm (mg per kg of water). Plankton concentrate it 200-fold relative to water. Each of the three later trophic transfers (small fi... JEE Advanced level