Question

which particle - diagram shown above best represents the strongest intermolecular force between two ethanol, c₂h₆o, molecules? diagram 1 because it shows hydrogen bonds forming between hydrogen atoms from different ethanol molecules. diagram 1 because it shows strong, directional dipole - dipole forces between two polar ethanol molecules. diagram 2 because it shows the formation of a hydrogen bond between an o atom bonded to an h atom with an o atom from another molecule. diagram 2 because it shows the dipole from an ethanol molecule inducing a dipole in another ethanol molecule.

Explanation:

Hydrogen - bonding is the strongest intermolecular force in ethanol ($C_2H_5OH$). It occurs when a hydrogen atom bonded to a highly electronegative atom (such as oxygen) is attracted to an electronegative atom in another molecule. Diagram 1 shows the formation of hydrogen - bonds between different ethanol molecules as the hydrogen atom attached to the oxygen in one ethanol molecule is attracted to the oxygen in another ethanol molecule. Dipole - dipole forces are weaker than hydrogen bonds for ethanol, and induced - dipole forces are even weaker.

Answer:

A. Diagram 1, because it shows hydrogen bonds forming between hydrogen atoms from different ethanol molecules.