At ambient temperature, F₂ and Cl₂are both gases while Br₂ is a liquid and I₂ is a solid. This is due to ________ A)dipole-dipole forces increasing with increasing molecular weight. B)dispersion forces increasing with increasing molecular weight. C)molecule polarity increasing with increasing molecular weight. D)both dispersion and polarity increasing with increasing molecular weight. E)ion-dipole forces increasing with increasing molecular weight.

Question

Quizplus · Accepted Answer

The difference in physical state of these four elements can be attributed to the intermolecular forces within the substances. In particular, the strength of dispersion forces between the molecules increases with increasing molecular weight, which is why the heavier molecules such as Br and I are liquid and solid at room temperature, respectively. Therefore, choice B is the best choice as it correctly identifies dispersion forces as the main reason for the differences in physical state.

At Ambient Temperature, F2 and Cl2 are Both Gases While

At Ambient Temperature, F₂ and Cl₂are Both Gases While