Question
In the reaction, \[C{{l}_{2}}+C{{H}_{4}}\xrightarrow{H\upsilon }C{{H}_{3}}Cl+HCl\] presence of a small amount of oxygen
A.
increases the rate of reaction for a brief period of time
B.
decreases the rate of reaction for a brief period of time
C.
does not affect the rate of reaction
D.
completely stops the reaction
Answer :
decreases the rate of reaction for a brief period of time
Solution :
Halogenation of alkanes follows free radical mechanism and presence of a small amount of oxygen can slow down the reaction for a period of time depending upon the amount of oxygen. Oxygen reacts with methyl free radical to form less reactive free radical and acts as an inhibitor.