Q. 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?
(a) Both Statement II and Statement III are correct and both of them explain Statement I
(b) Both Statement II and Statement III are correct but only one of them explains Statement I
(c) Only one of the Statements II and III is correct and that explains Statement I
(d) Neither Statement II nor Statement III is correct
Correct Answer – (a) Both Statement II and Statement III are correct and both of them explain Statement I
UPSC Prelims 2025 GS Paper's Solution
Explanation :
Statement II is true – activated carbon has a highly porous structure (surface areas up to 1 000–2 000 m²/g) that makes it an excellent adsorbent for heavy‐metal ions and other dissolved pollutants. Statement III is also true – one can prepare activated carbon cheaply by pyrolyzing and activating high‐carbon wastes (coconut shells, nutshells, sawdust, sewage sludge, etc.).
Together, (II) explains why activated carbon is so effective at removing contaminants (its huge surface area and affinity for metals), and (III) explains why it is an attractive (i.e. low‐cost, sustainable) tool, thus both support Statement I.
