JEE Main 2016 — Environmental Chemistry Question with Solution

Out of the given options, the substance that is a better strategy to control environmental pollution in dry cleaning is carbon dioxide (CO₂).

Option A: Tetrachloroethylene, also known as perchloroethylene (PERC), is a commonly used solvent in dry cleaning. However, it is a hazardous air pollutant and a potential human carcinogen. Its use has been restricted or banned in many countries due to its harmful effects on the environment and human health.

Option B: Carbon dioxide is a more environmentally friendly alternative to traditional dry cleaning solvents like PERC. CO₂ is a non-toxic, non-flammable, and readily available gas that can be used as a cleaning solvent when it is in its supercritical state. CO₂ dry cleaning is a "green" process that does not produce hazardous waste or emit harmful air pollutants.

Option C: Sulphur dioxide (SO₂) is a common air pollutant that is emitted from the burning of fossil fuels. It is not used as a dry cleaning solvent, and its use would not be an effective strategy to control pollution in dry cleaning.

Option D: Nitrogen dioxide (NO₂) is also a common air pollutant that is emitted from the burning of fossil fuels. It is not used as a dry cleaning solvent, and its use would not be an effective strategy to control pollution in dry cleaning.

Therefore, the correct option is Carbon dioxide.