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Bonding A level chem - AQA

If you melt or boil a simple covalent compound u overcome the intermolecular forces but if its a giant covalent substance do u overcome the covalent bonds or break the covalent bonds? Because some textbooks use the term overcome and some use break. But I was told u cant break intermolecular forces u overcome them so is this the same with covalent bonds?
Reply 1
When a compound with a giant covalent structure melts, the covalent bonds between atoms are broken.
Reply 2
Original post by Rohan007best
If you melt or boil a simple covalent compound u overcome the intermolecular forces but if its a giant covalent substance do u overcome the covalent bonds or break the covalent bonds? Because some textbooks use the term overcome and some use break. But I was told u cant break intermolecular forces u overcome them so is this the same with covalent bonds?

If you melt/ boil a simple covalent structure, you are OVERCOMING the intermolecular forces (e.g. van Der Waals) between the molecules
But if you melt/boil a giant covalent structure, you are BREAKING the many strong covalent bonds
Mark schemes are very particular about wording (i.e. if you say you are BREAKING the intermolecular forces, you will usually receive 'chemical error' and get an automatic zero for that question) so be careful

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