The chemical added to petrol to prevent the deposition of lead in the combustion chamber is ............... .

In which of the following substances is the carbon atom arranged in a regular tetrahedral structure?

Arrange the following in increasing order of boiling point.
$(i)$ methane,butane,propane,pentane,ethane.
$(ii)$ $n$-pentane,neo-pentane,iso-pentane.
$(iii)$ ethane,$2$-methyl propane,propane,$n$-butane.
$(iv)$ $2$-methyl pentane,$2,2$-dimethyl butane,$2,2$-dimethyl propane.

Hydrocarbon $(A)$ reacts with bromine by substitution to form an alkyl bromide,which by Wurtz reaction is converted to a gaseous hydrocarbon containing less than four carbon atoms. $(A)$ is

When sodium propionate is heated with soda lime,the main product is

An alkyl bromide $(X)$ reacts with $Na$ in the presence of dry ether to form $4, 5-$diethyloctane. Compound $(X)$ is