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Connectivity chem

Help does my whiteboard answer get a mark..
It’s not the q I don’t get it’s just does connectivity matter in these qs… the markscheme is showing the H2 connected to the BENZENE ring but that’s incorrect no? Will I get the mark with both (whiteboard and markscheme) I do ocr a a level chemIMG_2618.jpegIMG_2620.jpeg
(edited 1 year ago)
Original post by Alevelhelp.1
Help does my whiteboard answer get a mark..
It’s not the q I don’t get it’s just does connectivity matter in these qs… the markscheme is showing the H2 connected to the BENZENE ring but that’s incorrect no? Will I get the mark with both (whiteboard and markscheme) I do ocr a a level chemIMG_2618.jpegIMG_2620.jpeg

Yours is fine :smile:
It is the C that is attached to the benzene ring, but seeing a CH3CH2- chain written as H3CH2C- can kind of look a bit confusing!
I tend to write CH3CH2 and then show the bond connecting the benzene to the carbon (I'll probably move the Hs down a little), looks a little wonky at times but then I know there's no ambiguity
Original post by bl0bf1sh
Yours is fine :smile:
It is the C that is attached to the benzene ring, but seeing a CH3CH2- chain written as H3CH2C- can kind of look a bit confusing!
I tend to write CH3CH2 and then show the bond connecting the benzene to the carbon (I'll probably move the Hs down a little), looks a little wonky at times but then I know there's no ambiguity


Thanksss 🤍🤍🤍
Just to clarify both get the mark right, the one on the markscheme even thoughconnectivity is wrong 😭
(edited 1 year ago)
Original post by Alevelhelp.1
Thanksss 🤍🤍🤍
Just to clarify both get the mark right, the one on the markscheme even thoughconnectivity is wrong 😭


Yep, although like I said you'd be best to show the connectivity correctly so there is no ambiguity (i.e. you won't lose marks for it looking like you think the benzene ring is attached to hydrogens instead of carbon), but keep the conventional order of atoms when you're writing the condensed structural formula so it's nice and easy to read. If it's a common small group (e.g. -CH3, -OH, -NH2, -COOH) by itself you're generally fine writing it in reverse, but with things like esters and ketones it can get a little confusing :smile:

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