Q.What is formalin?

The polar C=O bond gives aldehydes and ketones dipole-dipole intermolecular attraction, and lets their oxygen hydrogen-bond with water, making lower members of both series water-soluble (solubility falling as the non-bonding hydrocarbon portion grows with molecular mass); boiling points rise steadily up each homologous series, with a ketone running at or just above its isomeric aldehyde. Carboxylic acids go further: their -COOH lets two molecules pair into a hydrogen-bonded DIMER (two H-bonds at once), which persists even in the gas phase for acetic acid and roughly doubles the effective molecular size, giving carboxylic acids markedly higher boiling points than alkanes, ethers, alcohols, aldehydes or ketones of comparable mass. The …