Which of the following are the heteroatoms present in $CH_{3}-CH_{2}-O-CH_{2}-CH_{2}Cl$?
$(i)$ Oxygen
$(ii)$ Carbon
$(iii)$ Hydrogen
$(iv)$ Chlorine

$A$ carboxylic acid (molecular formula $C_{2}H_{4}O_{2}$) reacts with an alcohol in the presence of an acid catalyst to form a compound $'X'$. The alcohol on oxidation with alkaline $KMnO_{4}$ followed by acidification gives the same carboxylic acid $C_{2}H_{4}O_{2}$. Write the name and structure of $(i)$ carboxylic acid,$(ii)$ alcohol,and $(iii)$ the compound $'X'$.

Which functional group is attached to the hydrocarbon chain in soap?

State the valency of each carbon atom in $(i)$ an alkane and $(ii)$ an alkyne.

$A$ molecule of ammonia has the formula $NH_{3}$. Predict the total number of bonds present around the nitrogen atom.

State the two properties of carbon which make it unique among other elements. State the two uses of carbon which are based on its unique property.