Check the most important environmental science questions and answers for all classes and various competitive exams.
These environmental science questions (MCQ) are designed in a quiz-based format with multiple choices and an explanation for the answer.
Environmental Science Questions and Answers
1. Which of the following process unit is used for air pollution control in chemical plants?
A. Thermal Oxidizer
B. VPCU
C. Fluidized bed Combustion
D. None of these.
Answer with Explanation
Answer: Option A
Explanation: Thermal Oxidizer used in many chemical plants to control air pollution.
It helps to destroy hazardous air pollutants and volatile organic compounds at a high temperature and releases them into the atmosphere.
2. Full form of CTBT is;
A. Comprehensive Nuclear-Test-Ban Treaty.
B. Comprehensive Test Bank Trust.
C. Comprehensive Trust Ban Treaty.
D. Comprehensive Test Ban Trusty.
Answer with Explanation
Answer: Option A
Explanation: Comprehensive Nuclear-Test-Ban Treaty or CTBT bans nuclear explosive testing for everyone, everywhere, in all environments. CTBT makes it very difficult for countries to test or develop any nuclear weapon. The CTBT was opened for signature in 1996.
3. What is the full form of BOD?
A. Bacterial Oxygen Demand.
B. Biological Oxygen Demand.
C. Biological Oxide Demand.
D. None of these.
Answer with Explanation
Answer: Option B
Explanation: BOD or Biological Oxygen Demand indicates the amount of dissolved oxygen needed by biological microorganisms in the biological process of breaking down organic substances in water.
It is also called Biochemical oxygen demand.
4. How much percentage of nitrogen is in Earth’s Atmosphere?
A. 25%.
B. 12%.
C. 92%.
D. 78%.
Answer with Explanation
Answer: Option D
Explanation: Earth’s atmosphere consists of a layer of gases. It is known as air. The composition of Dry air contains; 78.09% of Nitrogen(N2), 20.95% of Oxygen (O2), 0.93% of Argon (Ar) and 0.04% of Carbon dioxide(CO2).
Also, it contains small amounts of other gases like; helium, neon, krypton, hydrogen and water vapour.
5. Full form of COD is;
A. Chemical Oxide Demand.
B. Chemical Oxygen Demand.
C. Chemical Ozone Demand.
D. None of these.
Answer with Explanation
Answer: Option B
Explanation:
No explanation for this question.
6. The disease “Itai Itai” is caused by;
A. Manganize.
B. Carbon.
C. Cadmium.
D. None of these.
Answer with Explanation
Answer: Option C
Explanation:
No explanation for this question.
7. Human beings can hear a range of sound frequencies between;
A. 20-20,000 Hertz.
B. 10-1,000 Hertz.
C. 1-100 Hertz.
D. 1-7 Hertz
Answer with Explanation
Answer: Option A
Explanation: 20-20,000 Hertz is the common human hearing range. Though it differs between individuals.
There are many animals that can hear beyond the range of human beings. For example, some whales can hear infrasonic sounds of 7 Hz in water, and some bats and dolphins can hear frequencies up to 100,000 Hz.
The researcher has also found that human beings can hear up to 200,000 Hz underwater, which is 10 times higher than the top frequency (20,000 Hz) a human can hear on land.
8. Which of the following energy sources is/are the alternative energy to fossil fuel?
A. Marine energy
B. Wind energy
C. Solar energy
D. All of these
Answer with Explanation
Answer: Option D
Explanation:
No explanation for this question.
9. What percentage of land area should remain covered by forest in India to maintain ecological balance?
A. 10%
B. 5%
C. 33%
D. None of these.
Answer with Explanation
Answer: Option C
Explanation: In the past, the British have introduced many scientific approaches to the development and management of the forest. But the first approach by the government was traced to National Forest Policy, 1894, which was revised in 1952. The policy focuses on the extension of forests and starting a green movement in the country.
This policy states that 33% of the geographical area should be covered by forest/trees. Also, 60% of the land area will be in the hills, and 20% will be in the plains.
Later the National Forest Policy was again revised by the policymakers in 1988, and they gave priority to the sustainable development of the forest.
10. First International Conference on Environment held on;
A. March,1968.
B. March,1970.
C. June,1970.
D. June,1972.
Answer with Explanation
Answer: Option D
Explanation: United Nations Conference on the Human Environment (also known as Stockholm Conference held in Stockholm, Sweden, from June 5-16 in 1972.
It was the first UN(United Nations) conference that focused on international environmental issues.
