ECAT (Engineering College Admission) Chemistry Environmental Chemistry — Set 3

Environmental Chemistry MCQs set 3 for ECAT (Engineering College Admission) Chemistry — 20 solved questions.

ECAT (Engineering College Admission) Chemistry Environmental Chemistry — Set 3

  1. Question 1

    Q1. The pE of a solution is a measure of its?

    • A) pH
    • B) Redox potential
    • C) Ionic strength
    • D) Buffer capacity

    Answer: Redox potential

    Explanation: pE is a measure of the tendency of a solution to donate or accept electrons, indicating its redox potential

  2. Question 2

    Q2. The main source of mercury pollution is?

    • A) Industrial emissions
    • B) Agricultural runoff
    • C) Domestic waste
    • D) Natural sources

    Answer: Industrial emissions

    Explanation: Industrial emissions, such as from coal-fired power plants, are a significant source of mercury pollution

  3. Question 3

    Q3. What is the purpose of wastewater treatment?

    • A) To remove pathogens
    • B) To remove nutrients
    • C) To remove organic matter
    • D) All of the above

    Answer: All of the above

    Explanation: Wastewater treatment aims to remove various pollutants, including pathogens, nutrients, and organic matter, to protect the environment

  4. Question 4

    Q4. The DO level in a water sample is 2 mg/L. What does it indicate?

    • A) Healthy aquatic life
    • B) Moderate organic pollution
    • C) Severe organic pollution
    • D) No organic pollution

    Answer: Severe organic pollution

    Explanation: Low DO levels indicate high organic pollution, as microorganisms consume DO while breaking down organic matter

  5. Question 5

    Q5. What is the effect of oil spills on aquatic life?

    • A) Increased biodiversity
    • B) Decreased DO levels
    • C) Physical smothering
    • D) All of the above

    Answer: All of the above

    Explanation: Oil spills can cause physical smothering, decreased DO levels, and toxicity, harming aquatic life

  6. Question 6

    Q6. The main cause of cultural eutrophication is?

    • A) Natural nutrient cycling
    • B) Agricultural runoff
    • C) Sewage and industrial waste
    • D) Both B and C

    Answer: Both B and C

    Explanation: Cultural eutrophication is caused by excess nutrient inputs from agricultural runoff, sewage, and industrial waste

  7. Question 7

    Q7. What is the purpose of adding chlorine to drinking water?

    • A) To remove hardness
    • B) To disinfect
    • C) To remove turbidity
    • D) To decrease pH

    Answer: To disinfect

    Explanation: Chlorine is added to drinking water as a disinfectant to kill pathogens and microorganisms

  8. Question 8

    Q8. The major cause of acid rain is the emission of which gas?

    • A) CO2
    • B) SO2
    • C) CH4
    • D) N2O

    Answer: SO2

    Explanation: SO2 reacts with water and oxygen to form sulfuric acid, a major component of acid rain.

  9. Question 9

    Q9. The BOD (Biochemical Oxygen Demand) of a water sample is a measure of its

    • A) Oxygen content
    • B) Organic matter content
    • C) pH level
    • D) Turbidity

    Answer: Organic matter content

    Explanation: BOD measures the oxygen consumed by microorganisms in breaking down organic matter.

  10. Question 10

    Q10. The process by which water moves through a plant, from the roots to the atmosphere, is called

    • A) Respiration
    • B) Photosynthesis
    • C) Transpiration
    • D) Evaporation

    Answer: Transpiration

    Explanation: Transpiration is the process of water movement through plants and its evaporation from aerial parts.

  11. Question 11

    Q11. The Montreal Protocol is an international agreement aimed at protecting the

    • A) Ozone layer
    • B) Climate
    • C) Biodiversity
    • D) Water resources

    Answer: Ozone layer

    Explanation: The Montreal Protocol targets the reduction of ozone-depleting substances.

  12. Question 12

    Q12. The major environmental impact of particulate matter (PM) is on

    • A) Human health
    • B) Climate change
    • C) Water quality
    • D) Soil quality

    Answer: Human health

    Explanation: Particulate matter can cause respiratory problems and other health issues.

  13. Question 13

    Q13. The pH of rainwater is typically around

    • A) 5.6
    • B) 7.0
    • C) 4.5
    • D) 8.0

    Answer: 5.6

    Explanation: Pure rainwater has a pH of around 5.6 due to the dissolution of CO2.

  14. Question 14

    Q14. The process of converting waste into energy is known as

    • A) Recycling
    • B) Composting
    • C) Waste-to-energy
    • D) Landfilling

    Answer: Waste-to-energy

    Explanation: Waste-to-energy involves burning waste to produce electricity or heat.

  15. Question 15

    Q15. The most significant factor affecting the self-purification capacity of a river is

    • A) Water temperature
    • B) Flow rate
    • C) pH level
    • D) Dissolved oxygen

    Answer: Flow rate

    Explanation: Flow rate influences the dilution and transport of pollutants.

  16. Question 16

    Q16. The term 'bioaccumulation' refers to the

    • A) Accumulation of pollutants in the environment
    • B) Accumulation of pollutants in living organisms
    • C) Breakdown of pollutants in the environment
    • D) Release of pollutants into the environment

    Answer: Accumulation of pollutants in living organisms

    Explanation: Bioaccumulation is the process by which substances, such as chemicals, gradually accumulate in living organisms.

  17. Question 17

    Q17. The major component of photochemical smog is

    • A) Ozone
    • B) NOx
    • C) SO2
    • D) CO

    Answer: Ozone

    Explanation: Ground-level ozone is a major component of photochemical smog, formed through the interaction of sunlight with pollutants.

  18. Question 18

    Q18. The environmental impact of a pollutant is determined by its

    • A) Concentration and persistence
    • B) Toxicity and bioaccumulation potential
    • C) Both A and B
    • D) Neither A nor B

    Answer: Both A and B

    Explanation: Both the concentration and persistence, and the toxicity and bioaccumulation potential, determine the environmental impact.

  19. Question 19

    Q19. The Kyoto Protocol is an international treaty aimed at reducing

    • A) Ozone-depleting substances
    • B) Greenhouse gas emissions
    • C) Persistent organic pollutants
    • D) Heavy metal emissions

    Answer: Greenhouse gas emissions

    Explanation: The Kyoto Protocol targets the reduction of greenhouse gas emissions.

  20. Question 20

    Q20. The term 'threshold limit value' (TLV) refers to the

    • A) Maximum allowable concentration of a pollutant in air
    • B) Minimum concentration of a pollutant that causes harm
    • C) Maximum concentration of a pollutant in water
    • D) Minimum concentration of a pollutant in soil

    Answer: Maximum allowable concentration of a pollutant in air

    Explanation: TLV is the maximum allowable concentration of a pollutant in the air that a worker can be exposed to without adverse health effects.