Consider the following statements :
Statement I :
Activated carbon is a good and an attractive tool to remove pollutants from effluent streams and to remediate contaminants from various industries.
Statement II :
Activated carbon exhibits a large surface area and a strong potential for adsorbing heavy metals.
Statement III :
Activated carbon can be easily synthesized from environmental wastes with high carbon content.
Which one of the following is correct in respect of the above statements?
Show answer
Answer: A. Statement I is correct: activated carbon is widely used to clean industrial effluents and remove contaminants. Statement II is correct and explains it: it has a very large surface area and adsorbs heavy metals and organic pollutants well. Statement III is correct and also explains it: it can be made cheaply from carbon-rich wastes such as coconut shells and agricultural residues, which makes it an attractive tool. So both explain Statement I.
Watch for: Statement III looks like an unrelated production fact, but it explains the 'attractive' part of Statement I.
Why the other options are wrong
- B. Wrong: low-cost synthesis from waste (III) also explains why it is 'attractive', so both explain I.
- C. Wrong: both Statement II and Statement III are correct.
- D. Wrong: both Statement II and Statement III are correct.
Source to check: NCERT Class XII Chemistry (pre-2023 editions), 'Surface Chemistry' (adsorption, activated charcoal)
Answer from the official UPSC key. Written and fact-checked by AI against the official key. Spotted a mistake? Report it.