-->

Electromagnetic Waves

Question
CBSEENPH12048025

Assertion:  UV radiation causes photodissociation of ozone into O2 and O, thus causing damage to the stratospheric ozone layer. 

Reason:  Ozone hole is resulting in global warming and climate change.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are true but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false

  • If both assertion and reason are false

Solution

C.

If assertion is true but reason is false

UV radiation does not cause photodissociation of ozone into O2 and O instead it takes pan in the formation of ozone into two steps. In the first step, UV radiation breaks apart the two atoms of oxygen and in the second step one of the liberated atoms ( O ) joins another oxygen molecule ( O2 ) to form ozone ( O3 )

          O2 UV radiation  O + O

           O2 + O UV radiation O3                                  ozone

human activities, the ozone layer in the stratosphere becomes start thinning which is also called ozone hole.  Ozone hole is resulting in rain failure, increase in radiation, cancers (skin) and reduction in crop production. Global warming and climate changes are mainly due to green-house gases ( CO2, NOx ).