In which of the following compounds,$-OH$ is the functional group?

What is formed when methanol reacts with carbon monoxide in the presence of an $I_2-Rh$ catalyst?

$(a)$ How is vinegar made?
$(b)$ What is glacial acetic acid? What is its melting point?
$(c)$ Why are carboxylic acids called weak acids?
$(d)$ Write the name and the formula of the two compounds formed when the ester $CH_{3}COOC_{2}H_{5}$ undergoes saponification.

An organic compound burns with a sooty flame. Is it a saturated or an unsaturated compound?

The first member of the alkyne homologous series is:

How would you bring about the following conversions? Name the process and write the reaction involved.
$(a)$ Ethanol to ethene.
$(b)$ Propanol to propanoic acid.
Write the reactions.