MCQ
Ozone depletion is occurring due to :
  • A
    $\text{PCB}$
  • B
    $\text{CO}$
  • C
    $\text{PAN}$
  • None of the above

Answer

Correct option: D.
None of the above
Ozone is the protective layer present in the stratosphere. The harmful ultraviolet radiation is absorbed by the ozone layer. They are carried high into the stratosphere by wind action. Depletion begins when $\text{CFC’s}$ get into the stratosphere. Ultraviolet radiation from the sun breaks up these $\text{CFCs}.$ The breaking up action releases chlorine atoms. Chlorine atoms react with ozone, starting a chemical cycle that destroys the good ozone in that area. It is not depleted by $\text{PCB},$ carbon monoxides, and $\text{PAN}$.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

In which molecule all bonds are not equal
At $1990\, K$ and $1\, atm$ pressure, there are equal number of $Cl _{2}$ molecules and $Cl$ atoms in the reaction mixture. The value $K _{ P }$ for the reaction $Cl _{2( g )} \rightleftharpoons 2 \,Cl _{( g )}$ under the above conditions is $x \times 10^{-1}$ The value of $x$ is ..........

(Rounded of to the nearest integer)

Which of the reaction defines $\Delta H_f^o$
Solid $Ba(NO_3)_2$ is gradually dissolved in $1.0 \times 10^{-4} \,M \,Na_2CO_3$  solution. At which concentration of $Ba^{2+}$ the precipition will begin? ( $K_{sp}$ $BaCO_3 = 5.1 \times 10^{-9}$)
Which of the following does not react with $PC{l_5}$
$18.72g$ of a substance $X$ occupies $1.81\ cm^3$. What will be its density measured in correct significant figures?
Aqueous solution of two compounds $M_1OH$ and $M_2OH$ are prepared in two different beakers if the $EN$ of $M_1 = 3.4, EN$ of $M_2 = 1.2, EN$ of $O = 3.5$ and $EN$ of $H = 2.1$, then nature of two solutions will be
Which of the following is an isomer of compound $1$ ?

$\underset{(1)}{\mathop{C{{H}_{3}}C{{H}_{2}}CHO}}\,$   

$\underset{(2)}{\mathop{\begin{matrix}
   O  \\
   ||  \\
   C{{H}_{3}}-C-C{{H}_{3}}  \\
\end{matrix}}}\,$

$\underset{(3)}{\mathop{C{{H}_{3}}-CH=CH-OH}}\,$

Most elements are solids at $25^\circ C$ and $1$ atm pressure, the exception being the $11$ elements that are gases and $2$ that are liquids. What $2$ elements are liquids?
$2-$ Butyne react with $Na$ in liquid Ammonia to form