Question

Which of the following statements regarding ozone is incorrect?

• A. Good ozone' is formed in the lower atmosphere (troposphere) that absorbs harmful $UV$ rays coming from Sun; 'bad ozone' is present in the upper part of atmosphere (stratosphere) that harms plants and animals
• B. The thickness of the ozone in a column of air from the ground to the top of the atmosphere is measured in terms of Dobson units (DU)
• C. Recognising the deleterious effects of ozone depletion, an international treaty, known as the Montreal Protocol, was signed at Montreal (Canada) in $1987$ (became effective in $1989$) to control the emission of ozone depleting substances
• D. None of these

Answer 1

Answer: (A)

Good ozone' is formed in the lower atmosphere (troposphere) that absorbs harmful $UV$ rays coming from Sun; 'bad ozone' is present in the upper part of atmosphere (stratosphere) that harms plants and animals

Answer 2

Answer (a) 'Good ozone' is formed in the lower atmosphere (troposphere) that absorbs harmful $UV$ rays coming from Sun; 'bad ozone' is present in the upper part of atmosphere (stratosphere) that harms plants and animals