Which isomer of hexane gives only two monochlorinated products?

$A$ compound $A$ contains $C$ and $H$ only and has a molecular mass of $72$. Its photochlorination gives a mixture containing only one monochloro and two dichloro hydrocarbons. What is its $IUPAC$ name?

When $sec$-butylcyclohexane reacts with bromine in the presence of sunlight,the major product is:

The alkane formed on heating sodium butanoate with sodalime is

Match the column $I$ with column $II$ to identify the products of oxidation of alkanes and mark the appropriate choice.

Column $I$	Column $II$
$A$. $(CH_3)_3CH + O_2 \xrightarrow{KMnO_4} (CH_3)_3COH$	$i$. $CH_3COOH + H_2O$
$B$. $2CH_4 + O_2 \xrightarrow[100 \ atm]{Cu/523 \ K} 2CH_3OH$
$C$. $CH_4 + O_2 \xrightarrow[\Delta]{Mo_2O_3} HCHO + H_2O$	$iii$. $2CH_3OH$
$D$. $CH_3-CH_3 + \frac{3}{2}O_2 \xrightarrow{(CH_3COO)_2Mn} CH_3COOH + H_2O$	$iv$. $HCHO + H_2O$

The number of possible constitutional isomers of an alkane with the formula $C_6H_{14}$ is: