Tag: ozone and its depletion

Questions Related to ozone and its depletion

Ozone is an important constituent of stratosphere because it:

zoology allotropy of oxygen ozone - a case study stratospheric pollution ozone and its depletion

  1. prevents the formation of smog over large cities

  2. removes poisonous gases of the atmosphere by reacting with them

  3. absorbs ultraviolet radiations which is harmful to human life

  4. destroys bacteria which are harmful to human life

Show answer
Correct Option: C
Explanation:
The stratospheric ozone layer absorbs ultraviolet light (UV) emitted by the sun. If the solar UV light were able to penetrate the stratosphere and troposphere and reach the earth’s surface, it would seriously damage our ecosystem.
And also it causes skin cancer, blindness, and cataracts.
Hence, the correct option is C.

Which of the following is responsible for peeling of ozone umbrella?

zoology allotropy of oxygen ozone - a case study stratospheric pollution ozone and its depletion

  1. PAN

  2. Coal burning

  3. CFCs

  4. ${CO} _{2}$

Show answer
Correct Option: C
Explanation:
$ The\quad correct\quad answer\quad is\quad "CFCs".$

$CFCs\quad drift\quad slowly\quad upward\quad to\quad the\quad stratosphere,where\quad they\quad are\quad broken\quad up\quad by\quad ultraviolet\quad radiation,releasing\quad chlorine\quad atoms,which\quad are\quad able\quad to\quad destroy\quad Ozone\quad molecules.The\quad chlorine\quad atom\quad then\quad reacts\quad with\quad anozone(O3)molecule\quad breaking\quad it\quad apart\quad and\quad so\quad destroying\quad the\quad ozone.$\\

$A\quad single\quad CFCs\quad molecule\quad can\quad destroy\quad 100,000\quad ozone\quad molecules.$

Which of the following statements is correct?

zoology allotropy of oxygen ozone - a case study stratospheric pollution ozone and its depletion

  1. Ozone hole is a hole formed in stratosphere from which ozone oozes out

  2. Ozone hole is a hole formed in troposphere from which ozone oozes out

  3. Ozone hole is thinning of ozone layer of stratosphere at some places

  4. Ozone hole means vanishing of ozone layer around the earth completely.

Show answer
Correct Option: C
Explanation:
The correct answer is Ozone hole is thinning of an ozone layer of the stratosphere at some places

The ozone hole is formed mainly from the two types of compounds which are responsible for the depletion of the ozone layer.
 These are:-
  • NO'S
  • CFC'S(Chlorofluorocarbons)
$N{ O } _{ 2 }+{ O } _{ 3 }\longrightarrow N{ O } _{ 2 }+{ O } _{ 2\\  }$
$C{ F } _{ 2 }C{ l } _{ 2 }\longrightarrow { CF } _{ 2 }Cl\quad +Cl$
$\dot { Cl } +{ O } _{ 3 }\longrightarrow Cl\dot { O } +{ O } _{ 2 }$
$Cl\quad +\dot { O\longrightarrow  } C\dot { l } +{ O } _{ 2 }$
These reactions occur in the stratosphere.