Rank Ne, HBr, CH ₃ OH, and Ar in order of increasing strength of cohesive forces (least to greatest). A) Ne

Question

Rank Ne, HBr, CH ₃ OH, and Ar in order of increasing strength of cohesive forces (least to greatest). A) Ne < HBr < CH₃OH < Ar B) Ar < CH₃OH < HBr < Ne C) Ne < Ar < CH3OH < HBr D) Ne < Ar < HBr < CH₃OH E) Ar < Ne < CH₃OH < HBr

Quizplus · Accepted Answer

Cohesive forces are the intermolecular forces that hold molecules of the same substance together. The strength of cohesive forces increases with the increasing magnitude of intermolecular forces. Therefore, we need to determine the types of intermolecular forces in each substance to rank them in order of increasing strength of cohesive forces. Ne is a noble gas and exists as individual atoms with weak London dispersion forces, which are the weakest intermolecular forces. Therefore, Ne has the weakest cohesive forces. HBr is a polar molecule with dipole-dipole and London dispersion forces. CH₃OH is also a polar molecule with dipole-dipole, hydrogen bonding, and London dispersion forces. Ar is a noble gas and exists as individual atoms with weak London dispersion forces. Therefore, the order of increasing strength of cohesive forces is Ne < Ar < HBr < CH₃OH. The best choice is D.

Rank Ne, HBr, CH 3 OH, and Ar

Rank Ne, HBr, CH ₃ OH, and Ar