Question

In which of the following substances are there strongest and weakest interparticle attractive forces: carbon monoxide, potassium chloride, water, methanol, sugar?

Answer 1

Out of all the given substances, the strongest interparticle attractive forces are present in Potassium chloride $\left(\mathrm{KCl}\right)$ and the weakest interparticle attractive forces exist in Carbon monoxide $\left(\mathrm{CO}\right)$.

Interparticle forces: The force of attraction between the particles of a substance.

• Solids have the strongest interparticle forces of attraction and gases have the weakest.
• As Carbon monoxide is a gas, it has the weakest force of attraction between the molecules. The molecules of carbon monoxide are held by weak forces of attraction that allow gases to randomly move.
• Water $\left({\mathrm{H}}_2\mathrm{O}\right)$ and Ethanol $\left({\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\right)$ have intermediate forces of attraction between their respective particles as they are liquids.
• Potassium chloride is an ionic compound and the oppositely charged ions of different particles are also held together with strong electrostatic forces.
• Sugar is also solid but it is a covalent compound where interparticle force is a weak vander waal's forces of attraction because it is not a polar molecule.