Which of the following substances produces an explosive upon decarboxylation?

The correct order of strengths of the carboxylic acids is:

The reaction $\text{Cyclopentanecarboxamide} \xrightarrow[\Delta ]{P_2O_5} A$. The product $A$ is:

Which of the following is most acidic?

The highest electrical conductivity of the following aqueous solutions is of

Identify the reagent used in the following reaction: $\text{Benzoic acid} \xrightarrow[\Delta]{\text{Reagent}} \text{Benzoyl chloride} + \text{Phosphorus oxychloride} + \text{Hydrogen chloride}$.