Consider the following statements : Chlorofluorocarbons, known as ozone-depleting substances, are used 1. in the production of plastic foams 2. in the production of tubeless tyres 3. in cleaning certain electronic components 4. as pressurizing agents in aerosol cans Which of the statements given above is/are correct?

Chlorofluorocarbons (CFCs) are versatile chemicals historically used across several industrial sectors. They are extensively used as foaming or blowing agents in the production of plastic foams, such as polyurethane and insulation products [5]. In the electronics industry, CFCs served as critical solvents for cleaning delicate electronic and metallic components due to their non-corrosive and stable nature [2]. Furthermore, they were widely employed as pressurizing agents (propellants) in aerosol cans for products like sprays and local anesthetics [7]. However, there is no established industrial use of CFCs in the production of tubeless tyres, which primarily utilize synthetic rubbers and carbon black. Due to their role in stratospheric ozone depletion, the Montreal Protocol has phased out these substances [5]. Therefore, statements 1, 3, and 4 are correct.

Sources

1. [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 19: Ozone Depletion > here it is used? > p. 268
2. [2] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 6: Environmental Degradation and Management > ozone depletion > p. 12
3. [6] https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/trichlorofluoromethane
4. [7] https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=00000MVI.TXT
5. [3] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 7: Climate Change > 2. greenhouse gases > p. 11
6. [4] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 28: International Organisation and Conventions > 28.20. KIGALI AGREEMENT > p. 409