The increasing number of CFC production for industrial use has been a major contributor to the depletion of ozone molecules in the stratosphere. When CFCs diffuses slowly to the atmosphere in the presence of UV light between 175 nm to 220 nm, the ozone layer decomposes. If 1 mole of CFCl3 (Freon - 110) has been released into the air, how many moles of oxygen is produced from the photodecomposition of ozone?
Correct answer: B. 2
- A. 1
- B. 2
- C. 3
- D. 4
Explanation
The photodecomposition of one molecule of CFCI3 can destroy one ozone molecule, as shown in the following equation:CFCI3 + UV light → CFCl2 + Cl•Cl• + O3 → ClO• + O2ClO• + O → Cl• + O2Therefore, for every mole of CFCI3 photodecomposed, one mole of ozone is destroyed. Therefore, if 1 mole of CFCI3 is released, 1 mole of ozone will be destroyed. Since each ozone molecule is composed of 2 oxygen atoms, 2 moles of oxygen will be produced from the photodecomposition of 1 mole of ozone. Therefore, the answer is B) 2.
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