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Secondary alcohol - Why??

A question says:
Compound X has a molecular formula of C5H12O and is a secondary alcohol
Draw the displayed formula for X

I drew propan-2-ol but it was wrong the only correct answer was 3-methylbutan-2-ol

Why is that?

(The question was from AQA June 2013 unit 2 question 5)b)i) )
Original post by Da Bee
A question says:
Compound X has a molecular formula of C5H12O and is a secondary alcohol
Draw the displayed formula for X

I drew propan-2-ol but it was wrong the only correct answer was 3-methylbutan-2-ol

Why is that?

(The question was from AQA June 2013 unit 2 question 5)b)i) )


If you drew a compound with only 3 carbons in it and the molecular formula given was C5H12O why do you think your answer was wrong?
Propan-2-ol has three carbons, youve got five to take into account
I've looked at the paper. It tells you that the alcohol is made by reacting 2-bromo-3-methylbutane with hydroxide. There can only be one answer.
Happy birthday
(edited 8 years ago)
Original post by Da Bee
A question says:
Compound X has a molecular formula of C5H12O and is a secondary alcohol
Draw the displayed formula for X

I drew propan-2-ol but it was wrong the only correct answer was 3-methylbutan-2-ol

Why is that?

(The question was from AQA June 2013 unit 2 question 5)b)i) )


Propan-2-ol only has 3 carbons and 8 hydrogens...
Reply 6
Oh nooooo sorry I was meant to type pentan-2-ol
Original post by Da Bee
Oh nooooo sorry I was meant to type pentan-2-ol


Which would be fine unless there was something else in the remainder of the question like teach chemistry has posted. If you were just asked to give a possible structure for a secondary alcohol with the formula C5H12O then pentan-2-ol or pentan-3-ol would be fine, you've been told as well it's formed from the reaction of 2-bromo-3-methylbutane with hydroxide, in which case the straight chain compound you've proposed wouldn't work.


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Reply 8
Original post by Stiff Little Fingers
Which would be fine unless there was something else in the remainder of the question like teach chemistry has posted. If you were just asked to give a possible structure for a secondary alcohol with the formula C5H12O then pentan-2-ol or pentan-3-ol would be fine, you've been told as well it's formed from the reaction of 2-bromo-3-methylbutane with hydroxide, in which case the straight chain compound you've proposed wouldn't work.


Posted from TSR Mobile


Ah that makes sense thank you!

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