Class 11 Chemistry - Chapter Hydrocarbons NCERT Solutions | Explain why the following systems are no
Explain why the following systems are not aromatic?
(i) For the given compound, the number of π-electrons is six. But only four π-electrons are present within the ring. Also there is no conjugation of π-electrons within the ring and the compound is not planar in shape. Hence, the given compound is not aromatic in nature.
(ii) For the given compound, the number of π-electrons is four. By Huckel's rule,
4n + 2 = 4
4n = 2
n = ½
For a compound to be aromatic, the value of n must be an integer (n = 0, 1, 2…), which is not true for given compound. Hence, it is non aromatic in nature.
(iii) For the given compound, the number of π-electrons is eight. By Huckel's rule,
4n + 2 = 8
4n = 6
n = 3/2
For a compound to be aromatic, the value of n must be an integer (n = 0, 1, 2…). Since the value of n is not an integer, the given compound is not aromatic in nature.
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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Write IUPAC names of the products obtained by the ozonolysis of the following compounds:
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(iii) 2-Ethylbut-1-ene
(iv) 1-Phenylbut-1-ene
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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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Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, E+
(a) Chlorobenzene, 2,4-dinitrochlorobenzene, p-nitrochlorobenzene
(b) Toluene, p-H3C-C6H4-NO2, p-O2N-C6H4-NO2.
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(iii) used to determine pressure volume work
(iv) whose value depends on temperature only. - Q:-
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Justify the position of hydrogen in the periodic table on the basis of its electronic configuration.
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