Class 11 Chemistry - Chapter Hydrocarbons NCERT Solutions | How do you account for the formation of
How do you account for the formation of ethane during chlorination of methane?
Chlorination of methane proceeds via a free radical chain mechanism. The whole reaction takes place in the given three steps.
Step 1: Initiation:
The reaction begins with the homolytic cleavage of Cl- Cl bond as:
Step 2: Propagation:
In the second step, chlorine free radicals attack methane molecules and break down the C- H bond to generate methyl radicals as:
These methyl radicals react with other chlorine free radicals to form methyl chloride along with the liberation of a chlorine free radical.
Hence, methyl free radicals and chlorine free radicals set up a chain reaction. While HCl and CH3Cl are the major products formed, other higher halogenated compounds are also formed as:
Step 3: Termination:
Formation of ethane is a result of the termination of chain reactions taking place as a result of the consumption of reactants as:
Hence, by this process, ethane is obtained as a by-product of chlorination of methane.
More Questions From Class 11 Chemistry - Chapter Hydrocarbons
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Addition of HBr to propene yields 2-bromopropane, while in the presence of benzoyl peroxide, the same reaction yields 1-bromopropane. Explain and give mechanism.
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An alkene 'A' on ozonolysis gives a mixture of ethanal and pentan-3-one. Write structure and IUPAC name of 'A'.
- Q:-
Write IUPAC names of the products obtained by the ozonolysis of the following compounds:
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(ii) 3,4-Dimethyl-hept-3-ene
(iii) 2-Ethylbut-1-ene
(iv) 1-Phenylbut-1-ene
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How would you convert the following compounds into benzene?
(i) Ethyne (ii) Ethene (iii) Hexane
- Q:-
Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?
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Arrange benzene, n-hexane and ethyne in decreasing order of acidic behaviour. Also give reason for this behaviour.
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Explain why the following systems are not aromatic?
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(a) Chlorobenzene, 2,4-dinitrochlorobenzene, p-nitrochlorobenzene
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Assign oxidation number to the underlined elements in each of the following species:
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(b) NaHSO4
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(f) NaBH4
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(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only. - Q:-
A liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
a) What is the initial effect of the change on vapour pressure?
b) How do rates of evaporation and condensation change initially?
c) What happens when equilibrium is restored finally and what will be the final vapour pressure? - Q:-
Justify the position of hydrogen in the periodic table on the basis of its electronic configuration.
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Assign oxidation number to the underlined elements in each of the following species:
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The reaction:
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