GATE ES format:mcq PYQs & Answers — Page 6

Questions 51–60 of 200. Imported answers require independent review unless marked reviewed.

Match the following and choose the correct option from the following

Type of reactor	Diagram
1. Plug flow reactor	x.
2. Continuously stirred tank reactor	y.
3. Batch reactor	z.

The stirrer symbol indicates stirrer for mixing (not to scale).

Your answerChoose one option.

1-x, 2-y, 3-z

1-z, 2-y, 3-x

1-y, 2-z, 3-x

1-x, 2-z, 3-y

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Multiple effect evaporator is commonly used, in the zero liquid discharge (ZLD) scheme, for ________

Your answerChoose one option.

oxidation of organic pollutants

precipitation of heavy metals

concentrating reverse osmosis (RO) reject salts

perform selective ion exchange

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Consider the following statements

P : According to the National Ambient Air Quality Standards (Central Pollution Control Board, Govt. of India, notification 2009), annual time weighted average PM₁₀ standard is more than PM₂.₅ standard.

Q : According to the National Air Quality Index released by Govt. of India in 2015, sub index value of PM₁₀ can be less than that of PM₂.₅.

Choose the correct option from the following

Your answerChoose one option.

P is TRUE; Q is FALSE

P is FALSE; Q is TRUE

P is TRUE; Q is TRUE

P is FALSE; Q is FALSE

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Which option gives the components that are most likely to be present in the segregated combustible fraction (SCF) separated from raw mixed municipal solid waste (MSW)?

Your answerChoose one option.

plastics, paper, rubber, metals

plastics, paper, leather, glass

plastics, leather, textiles, rubber

plastics, rubber, textiles, food waste

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Correctly match the sustainable development goal (SDG) with its theme

SDG	Theme
i. SDG 6	p. Good Health and Well-being
ii. SDG 11	q. Responsible Consumption and Production
iii. SDG 3	r. Sustainable Cities and Communities
iv. SDG 12	s. Clean Water and Sanitation

Your answerChoose one option.

i-q ii-r iii-p iv-s

i-s ii-r iii-p iv-q

i-s ii-r iii-q iv-p

i-p ii-q iii-r iv-s

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Choose the correct option regarding the Basel Convention

Your answerChoose one option.

Almost all the nations of the world assembled for the first time in the history to discuss and find out the solution for a common environment problem.

It was for formulating the strategies and guidelines to reduce CO₂ and CH₄ emissions to control the global warming.

It was for formulating the strategies and guidelines to control the release of acid gases that can cause acid rain in another country.

It was for formulating the strategies and guidelines for the trans-boundary movement of hazardous wastes.

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A researcher added certain amount of HgCl₂ to water at pH 10. He calculated the expected concentration of mercury in the water. He asked his student to measure the concentration. His student used an instrument that can measure only the free metal, Hg²⁺. The student observed that the concentration measured by him was significantly less than the concentration calculated by the researcher. How can he explain the paradox to the researcher?

Explanation 1: Significant fraction of the mercury would have changed phase from aqueous to gaseous phase, thus leaving less mercury in the water

Explanation 2: Fraction of the mercury added to water would have formed aqueous complexes

Explanation 3: Fraction of the mercury added to water could have precipitated

Choose the correct option from the following

Your answerChoose one option.

only Explanation 1 is correct

Explanations 1 and 2 are correct

Explanations 1 and 3 are correct

Explanations 2 and 3 are correct

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Correctly label the speciation diagram below:

Diagram for Environmental Science and Engineering question 37

Your answerChoose one option.

I= PO₄³⁻, II= HPO₄²⁻, III= H₂PO₄⁻, IV= H₃PO₄

I= H₃PO₄, II= HPO₄²⁻, III= H₂PO₄⁻, IV=PO₄³⁻

I=H₃PO₄, II=H₂PO₄⁻, III=HPO₄²⁻, IV=PO₄³⁻

I= PO₄³⁻, II= H₂PO₄⁻, III= H₃PO₄, IV=HPO₄²⁻

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Consider the following statements on microbial metabolism (i) Utilization of carbon for cell synthesis is termed as anabolism. (ii) During catabolism, adenosine triphosphate (ATP) is converted into adenosine diphosphate (ADP). Choose the correct option from the following

Your answerChoose one option.

(i) and (ii) are correct

(i) and (ii) are incorrect

(i) is correct and (ii) is incorrect

(i) is incorrect and (ii) is correct

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Consider the following figure of an activated sludge process (ASP), depicting the flow (

), substrate (

), and microorganism concentration (

) at various points in the system, where subscripts “0”, “r”, “w”, “e”, and “i” indicate influent, recycle line, wastage, effluent, and flow from aeration tank to settling tank, respectively. Note that influent to the ASP has microbes too. V is volume of aeration tank.

Diagram for Environmental Science and Engineering question 39

Choose the correct option for net rate of formation of microorganisms in the system at steady state, from the following

Your answerChoose one option.

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GATE ES format:mcq PYQs

Question 18

Question 19

Question 20

Question 21

Question 22

Question 23

Question 36

Question 37

Question 38

Question 39