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| 16322836812 | Although Phosphine molecules contain hydrogen atoms, there is no hydrogen bonding between phosphine molecules, why? (1) | Answer shown above. |  | 0 |
| 16322836813 | What are the three types of intermolecular forces? | • van der Waals (induced dipole-dipole) • dipole-dipole (permanent) • H-bonding | 1 | |
| 16322838384 | What are van der Waals forces? | • Temporary dipoles between electrons in an atom • Causing an overall attraction • Bigger molecule = more e- --> stronger vdw |  | 2 |
| 16322836814 | What are dipole-dipole forces? | • Permenant dipoles, one of the atoms in the molecule (e.g a halide such as chlorine) is more electronegative (tendancy to attract a shared pair of electrons in a covalent bond) so forms a dipole-dipole molecule which is permenant. |  | 3 |
| 16322836815 | What are Hydrogen Bonds? | • Containing O, N, or F, which must be bonded to H • Hydrogen's delta positive being attracted to the loan pairs (which are negative) of another molecule. (bottom right F must have 2 more loan pairs) |  | 4 |
| 16322836816 | Explain why iodine has a higher melting point than fluorine (2) | Shown above. |  | 5 |
| 16322836817 | Boiling points of fluorine and hydrogen fluoride: -188c and 19.5c respectively Explain, in terms of bonding, why the boiling point of fluorine is very low (2) | Shown above. |  | 6 |
| 16322836818 | Draw H-bonding of hydrogen fluoride (3) | Shown above. |  | 7 |
| 16322836819 | Explain the shape of the graph in terms of bonding. | The H20 and HF have H-bonding, explaining why they have such high melting points as it takes more energy to break. The reason the other molecules begin to increase is because they have van der waals forces, which are much weaker, and increase in boiling points as the molecules get bigger as they have more electrons therefore more induced dipoles. |  | 8 |
