In the given reactions: (i) CH3BrNa,ether−−−−−→XBr2−−→hvYNa,ether−−−−−→Z (ii) CH3COOHNaOH−−−−→XNaOH−−−−→CaOYBr2−−→hvZ Identify X,Y and Z.
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Solution
The correct option is D(i)X=CH3CH3;Y=CH3CH2Br;Z=CH3CH2CH2CH3(ii)X=CH3COONa;Y=CH4;Z=CH3Br
(i)
(a) When methyl bromide is treated with sodium metal in presence of dry ether, coupling takes place to give ethane. Reaction is known as Wurtz's reaction and also called as coupling reaction of alkyl halide.
CH3BrNa,ether−−−−−→CH3−CH3
Thus, X is CH3CH3.
(b)The reaction of ethane with bromine called a substitution reaction.
CH3−CH3Br2−−→hνCH3CH2Br
Thus, Y is CH3CH2Br.
(c) Next reaction is also Wurtz's reaction and will form butane.
CH3CH2BrNa,ether−−−−−→CH3−CH2−CH2−CH3
Thus, Z is CH3CH2CH2CH3.
(ii)
(a) When NaOH added to acetic acid, they react to form sodium acetate and water. This is a typical acid + base neutralization reaction.
CH3COOHNaOH−−−−→CH3COONa+H2O
Thus, X is CH3COONa.
(b) When sodium acetate is treated with soda lime, decarboxylation takes place and CO2 is eliminated from the sodium acetate.
CH3COONaNaOH−−−−→CaOCH4+Na2CO3
Thus, Y is CH4.
(c) This reaction between methane and bromine happens in the presence of ultraviolet light - typically sunlight. This is a good example of a photochemical reaction.