A mixture of calcium sulphate and camphor can be separated by- 
1. Filtration
2. Evaporation
3. Sublimation
4. Chromatography

A gas among the following that can be absorbed by potassium hydroxide is -
1. Carbon dioxide
2. Silicon dioxide
3. Hydrogen
4. Carbon monoxide 

Which of the following acid can be used for the acidification of sodium extract for testing sulphur?

1. Sulphuric acid
2. Acetic acid
3. Nitric acid
4. Hydrochloric acid

0.3780 grams of an organic chloro compound gave 0.5740 grams of silver chloride in Carius estimation. % of chlorine present in the compound is -

In the Carius method, 0.468 grams of an organic sulphur compound gives 0.668 grams of barium sulphate.  The percentage of sulphur in the given compound is -

The most stable carbocation among the following is-
1. \(({CH_3})_3C\overset{+}{C}H_2\)
2. \(({CH_3})_3\overset{+}{C}\)
3. \({CH_3}CH_2\overset{+}{C}H_2\)
4. \(({CH_3})\overset{+}{C}HCH_2CH_3\)

${\mathrm{O}}_2{\mathrm{NCH}}_2{\mathrm{CH}}_2{\mathrm{O}}^{-}$ is more stable than ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{O}}^{-}$ because :

Alkyl groups act as electron donors when attached to a π system due to:

An electrophile among the following is :

Which of the following reactions is an elimination reaction?