To arrive at the molecular formula and at the structural formula the different steps involved are (a) Qualitative analysis, (b) Quantitative analysis In the qualitative analysis the different steps involved are (a) Extra element detection (b) Functional group analysis In the quantitative analysis the percentage of every element is determined and then the emperical and molecular formulae are determined. Both these are followed bystructural elucidation. Which of the following reagents can be used to identify benzene in on go?

To arrive at the molecular formula and at the structural formula the d

1.	To arrive at the molecular formula and at the structural formula the different steps involved are (a) Qualitative analysis, (b) Quantitative analysis In the qualitative analysis the different steps involved are (a) Extra element detection (b) Functional group analysis In the quantitative analysis the percentage of every element is determined and then the emperical and molecular formulae are determined. Both these are followed bystructural elucidation. Which of the following reagents can be used to identify benzene in on go?
Answer» Bromine WATER test `CHCl_(3)+AlCl_(3)` (anhydrous) test `I_(2)+NaOH` No test is available Solution :All ARENES give orange to red colour upon treatment with CHLOROFORM and anhydrous aluminium chloride. These are due to the formation of triaryl methyl carbocation which is formed by Friedal-Crafts REACTION by a transferred of `H^(-)` ion i.e., Napththalence `to` BLUE colour Anthracene `to` green colour PHenanthrene `to` purple colour Hence choice (b) is correct. (a) is incorrect. Benzene does not show `Br_(2)` water test as it does undergo addition reaction. (c) is wrong. Benzene does not show iodoform test nor any reaction with `I_(2)+NaOH`