The name of the compound $CH_{3}-CH_{2}-CHO$ is

Give names of the following:
$(a)$ An alcohol containing $4$ carbon atoms.
$(b)$ An acid with $5$ carbon atoms.
$(c)$ Simplest ketone. Define functional group in a carbon compound. Mention names of any three functional groups with their formulae and example.

Which among the following are unsaturated hydrocarbons?
$(i) H_3C - CH_2 - CH_2 - CH_3$
$(ii) H_3C - C \equiv C - CH_3$
$(iii) H_3C - CH(CH_3) - CH_3$
$(iv) H_3C - C(CH_3) = CH_2$

Which of the following functional groups is present in aldehyde compounds?

Define homologous series of organic compounds. Mention any two characteristics of homologous series.

The name of the compound $CH_{3}-CH_{2}-CHO$ is