Question

Which notion is incorrect?

A. Dispersion forces are present in all molecular substances.
B. The greater the dipole moment, the stronger the dipole-dipole forces.
C. The polarizability of elongated molecules is greater than that of compact, more spherical molecules.
D. London dispersion forces weaken in the order Xe < Kr < Ar
E. Hydrogen bonding leads to the strongest intermolecular forces.

Answer 1

D. London dispersion forces weaken in the order Xe < Kr < Ar is an incorrect order, the correct order of London dispersion forces weaken in the order Ar < Kr < Xe.

Step-by-step explanation:

A. Dispersion forces are present in all molecular substances.

is a correct statement London dispersion forces are weak intermolecular forces found in all molecular substances.

B. Clearly, greater the dipole moment, greater will be dipole-dipole forces. Hence true.

C) The polarizability of elongated molecules is greater than that of compact, more spherical molecules. The more elongated the molecule is more will be its ability to get polarized.

D. London dispersion forces weaken in the order Xe < Kr < Ar is an incorrect order, the correct order of London dispersion forces weaken in the order Ar< Kr < Xe.

E) Hydrogen bonding leads to the strongest intermolecular forces is also a correct statement. Hydrogen bonding leads to increase in boiling point.