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GCSE Chemistry - covalent bond

since covalent bond is formed between 2 non-metal atoms, which then makes it stable once 2 atoms join. Does it mean that it occurs between positive ions so that there are equal number of electrons and protons between these atoms, which makes it stable?? If so, shouldnt it be described that covalent bonds form between cation and not atom, more specifically?

Thanks :smile:
(edited 1 year ago)
Original post by BrightBlueStar11
since covalent bond is formed between 2 non-metal atoms, which makes it stable. Does it mean that it occurs between positive ions so that there are equal number of electrons and protons between these atoms, which makes it stable??

Thanks :smile:

No. Generally, if you tried to put two positive ions close enough together to attempt to bond them, they’d repel away from each other.

Also, for the purposes of GCSE, positive ions are usually metal cations without enough outer electrons left to form a covalent bond.
Original post by TypicalNerd
No. Generally, if you tried to put two positive ions close enough together to attempt to bond them, they’d repel away from each other.

Also, for the purposes of GCSE, positive ions are usually metal cations without enough outer electrons left to form a covalent bond.

thanks,

but i dont understand how when 2 atoms that are stable (same no. of protons and electrons) join together, its outcome is still stable? since they will have more electrons (thus exceeding the no. of protons), shouldnt they be negatively charged, which shouldnt be described as stable?
(edited 1 year ago)
Original post by BrightBlueStar11
thanks,

but i dont understand how when 2 atoms that are stable (same no. of protons and electrons) join together, its outcome is still stable? since they will have more electrons (thus exceeding the no. of protons), shouldnt they be negatively charged, which shouldnt be described as stable?


It’s not to do with the numbers of protons and electrons being even. In an atom, this has already been achieved, as suggested by the fact that the charges of the protons and electrons have cancelled out, hence the neutral charge.

An atom is (for the purposes of GCSE) stabilised when it has an octet (8 outer electrons), or has emptied it’s outermost shell.
(edited 1 year ago)
Original post by TypicalNerd
It’s not to do with the numbers of protons and electrons being even. In an atom, this has already been achieved, as suggested by the fact that the charges of the protons and electrons have cancelled out, hence the neutral charge.

An atom is (for the purposes of GCSE) stabilised when it has an octet (8 outer electrons), or has emptied it’s outermost shell.


So, when you say atom is stabilised, it isnt referring to its relative charge? if so, what is it referring to?

sorry just started chemistry revision lol
Reply 5
Original post by BrightBlueStar11
So, when you say atom is stabilised, it isnt referring to its relative charge? if so, what is it referring to?

sorry just started chemistry revision lol

it refers to the fact that the atoms have a full outer shell and therefore are unlikely to react with anything. it doesn't refer to the relative charge.
Original post by zeasea
it refers to the fact that the atoms have a full outer shell and therefore are unlikely to react with anything. it doesn't refer to the relative charge.


thanks,

so there are two concepts when you use the term "stability", one has to do with its relative charge and another has to do with its outer shell having 8 electrons??
Original post by zeasea
it refers to the fact that the atoms have a full outer shell and therefore are unlikely to react with anything. it doesn't refer to the relative charge.

Couldn’t have put it better myself.
Original post by BrightBlueStar11
thanks,

so there are two concepts when you use the term "stability", one has to do with its relative charge and another has to do with its outer shell having 8 electrons??

It’s all about the full outer shell.

Think about it. With ionic compounds, metals lose electrons, because their second-from-outermost shell (which is full) becomes their outer shell and nonmetals that gain electrons fill out their outer shells. With covalent bonding, pairs of electrons are shared, so that the outer shells overlap and fill out. This has nothing to do with relative charge.
(edited 1 year ago)
Reply 9
also, i've seen you posting quite a bit recently and i'd like to suggest some other resources that might help you:
- bbc bitesize - https://www.bbc.co.uk/bitesize/levels/z98jmp3
- primrose kitten on youtube - https://www.youtube.com/c/PrimroseKittenScience

both of these are great at explaining concepts, and bbc bitesize also allows you to take a quiz based on each topic.
if your school gives you access to them, i would also highly recommend actually using gcsepod and collinsconnect - collinsconnect has entire textbooks available digitally for you, and gcsepod is great for bursts of revision.
(edited 1 year ago)

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