Question

Identify the likely kinds of intermolecular forces in each of the following substances.PART AAl2O3, F2, H2O, Br2, ICl, and NaCl.THE ANSWER CHOICES FOR EACH ONE ARE (NOTE: THEY'RE THE SAME FOR EACH ONE):

a. dispersionb. ionicc. dipole-dipoled. H-bondingPART B. Using your knowledge of the relative strengths of the various forces, rank the substances in order of decreasing of their normal boiling points. RANK COMPOUNDS IN ORDER OF DECREASING OF THEIR NORMAL BOILING POINTS. (***NOTE: RANK FROM HIGHEST BP TO LOWEST BP***)Al2O3, F2, H2O, Br2, ICl, and NaCl.

Answer 1

Al2O3>NaCl>H2O>ICl>Br2>F2

Step-by-step explanation:

The stronger the intermolecular forces, the higher the boiling point will be. Ionic bonds are stronger than any of the intermolecular forces; thus, the ionic compounds will have the highest boiling points. Al2O3 has a higher boiling point than NaCl because it has the greater lattice energy. Hydrogen bonds are stronger than dipole-dipole forces, and dipole-dipole forces are stronger than dispersion forces. Therefore, H2O will have a higher boiling point than ICl , and Br2 and F2 will have the lowest boiling points. However, Br2 has a higher boiling point than F2 because the Br2 molecule is larger and more polarizable.

Answer 2

Al2O3 and NaCl-ionic

F2 and Br2- dispersion

ICl-dipole-dipole

H2O-Hydrogen bond

order of boiling points

Nacl>Al2O3>H2O>ICl>Br2>F2

Step-by-step explanation:

Al2O3 and NaCl has the highest boiling points as they are ionic substances known to have very high boiling points. The boiling point of NaCl is greater than that of Al2O3 because in the former, the bonding is purely ionic while there is some covalent contribution in the later. The boiling point of H2O is high because of Hydrogen bonding. The permanent dipole in ICl also elevates its boiling point. The boiling point of Br2 is greater than that of F2 because Br2 is larger that F2 hence posses greater inter molecular interaction.