What is the general molecular formula for a cycloalkane?

The suitable reagents for the conversion of methane into methyl iodide are

The $4^{th}$ higher homologue of ethane is

How many chiral compounds are possible on monochlorination of $2$-methylbutane?

Which of the following compounds does not give different isomers on monochlorination?

Identify all the possible monochloro structural isomers expected to be formed on free radical monochlorination of $(CH_3)_2CHCH_2CH_3$.