When chlorine gas reacts with methane, the product formed is a) CHCl b) CH2Cl c) CH3Cl d) CH4Cl
The Correct Answer and Explanation is :
The correct answer is (c) CH₃Cl (Methyl chloride).
Explanation:
When chlorine gas (Cl₂) reacts with methane (CH₄), a substitution reaction occurs. This reaction is an example of a free radical substitution reaction, which takes place in the presence of ultraviolet (UV) light or high temperatures.
Stepwise Reaction Mechanism:
- Initiation (Formation of Free Radicals):
- Under UV light, chlorine molecules (Cl₂) undergo homolytic fission, breaking into two chlorine radicals (Cl•):
[
Cl_2 \xrightarrow{UV} 2Cl•
]
- Propagation (Radical Chain Reaction):
- A chlorine radical reacts with methane, abstracting a hydrogen atom and forming a methyl radical (CH₃•):
[
CH_4 + Cl• \rightarrow CH_3• + HCl
] - The methyl radical then reacts with another chlorine molecule, forming methyl chloride (CH₃Cl) and generating another chlorine radical:
[
CH_3• + Cl_2 \rightarrow CH_3Cl + Cl•
] - This newly formed Cl• continues the chain reaction, leading to further substitution if excess chlorine is present.
- Termination (Stopping the Chain Reaction):
- The reaction stops when two free radicals combine to form a stable molecule:
[
Cl• + Cl• \rightarrow Cl_2
]
[
CH_3• + Cl• \rightarrow CH_3Cl
]
[
CH_3• + CH_3• \rightarrow C_2H_6 (ethane)
]
Final Product:
- The primary product is methyl chloride (CH₃Cl).
- If excess chlorine is present, further chlorination can lead to dichloromethane (CH₂Cl₂), chloroform (CHCl₃), and carbon tetrachloride (CCl₄).
Thus, the correct answer is CH₃Cl.
Now, I will generate an image representing this reaction.
Here is the generated image illustrating the chlorination of methane, showing the reaction mechanism with labeled molecular structures. Let me know if you need any modifications or further explanations!