Oxalic acid reacts with concentrated $H_2SO_4$ to produce a mixture of two gases. When this mixture is passed through caustic potash,one of the gases is absorbed. What substance is formed by the absorption of the gas in caustic potash?

Most acidic among the given acids is:

Identify $C$ in the following sequence of reactions:
$2\text{-methylcyclohexanecarboxylic acid}$ $\xrightarrow{SOCl_2} A$ $\xrightarrow{NH_3} B$ $\xrightarrow{P_4O_{10}, \text{heat}} C(C_8H_{13}N)$

Which of the following compounds would you expect to be the strongest carbon acid?

Among the following,which is most highly ionized in water?

Two statements are given below:
Statement $I:$ The melting point of monocarboxylic acids with an even number of carbon atoms is higher than that of acids with an odd number of carbon atoms immediately below and above it in the series.
Statement $II:$ The solubility of monocarboxylic acids in water decreases with an increase in molar mass.
Choose the most appropriate option.