Help with exam question?! (1 Viewer)

SuchSmallHands

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Hey so this was a question in my HSC chem half yearly, answer is A. Can anyone explain why?
Thanks :)
 

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iStudent

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There are 6 carbon atoms in the longest chain so by the process of elimination it has to be A (it's the only one that has a 'hex..' in its name)
also, it's hexan- 3-ol because the OH group is on the third carbon atom counting from the shortest end.
does that explain it?
 

SuchSmallHands

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But the six carbons aren't all in a chain? Isn't the last carbon a methyl group? Or am I just being dumb?
 

photastic

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But the six carbons aren't all in a chain? Isn't the last carbon a methyl group? Or am I just being dumb?
A methyl group would only occur in the middle of the chain. The last one is part of the chain so its should be A, think like the game snakes, all this chain did was move its head down. Methyl groups are branches of the long chain.
 

Machiavelli1

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A methyl group would only occur in the middle of the chain. The last one is part of the chain so its should be A, think like the game snakes, all this chain did was move its head down. Methyl groups are branches of the long chain.
There are 6 carbon atoms in the longest chain so by the process of elimination it has to be A (it's the only one that has a 'hex..' in its name)
also, it's hexan- 3-ol because the OH group is on the third carbon atom counting from the shortest end.
does that explain it?
I concur with both.
 

strawberrye

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Just to add on-practising more of these types of questions will enable you to get better at them through time:)
 

SuchSmallHands

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Just to add on-practising more of these types of questions will enable you to get better at them through time:)
I can do them fine normally, I just didn't know that if a branch is on the end it's considered part of the main chain :)
 

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