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Using your knowledge of chemistry

The melting point of non-metal elements depends on structure and bonding
Using your knowledge of chemistry, comment on this statement
Reply 1
Non metals usually have weak intermolecular forces and have simple molecular structures due to the covalent bonds and so they have low melting point
Non metals such as diamond on the other hand have stronger bonds as they have a giant covalent structure so they have higher melting points
It would also be good to state the strength of covalent bonds in relation to the intermolecular forces. Depending on how many marks also state the three different types of intermolecular forces that you've learnt thus far (VdW, pd-pd, H-bonding). Hope that helps!
Reply 4
Non-Metals generally have weak intermolecular forces of attraction (Van der Waals forces) between simple molecules, except for C, Si and B which form a covalent network and are held together by very strong covalent bonds.

Going across period 3 melting point generally decreases, except for sulphur and phosphorus being the other way around. This is due to sulfur forming a molecule with 8 atoms, phosphorus with 4, chlorine forms a diatomic molecule and argon a monoatomic molecule. Therefore even though as you go across the group electrons increase, sulfur has the highest melting point as it has 128 electrons to argons monoatomic 18. More electrons, more london dispersion forces the higher the melting point.

Going down the group as electron shells increase the added electrons increase the strength of London dispersion forces, increasing melting point.

Some non-metals have permanent-dipole permanent-dipole forces, (as well as LDF), between the molecules due to their difference in electronegativities, increasing their melting point.

Nitrogen, oxygen and fluorine form hydrogen bonds due to their large difference in electronegativity with hydrogen, increasing their melting points further.

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