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Organic chem.

Q.In the mass spectrum of an organic compound, the molecular ion occurs at m/e = 86.
Which of the following could be the empirical formula of the compound?
A C6H14
B C5H10N
C C5H12O
D C5H7F
Original post by All rounder
Q.In the mass spectrum of an organic compound, the molecular ion occurs at m/e = 86.
Which of the following could be the empirical formula of the compound?
A C6H14
B C5H10N
C C5H12O
D C5H7F


What do you think you should do?
D
Ar-> C5=60, H7=7,F=19
So when you add them up, it =86
Reply 3
But u would get the same for A C5H14
but the answer is D but idk how?
Original post by All rounder
But u would get the same for A C5H14
but the answer is D but idk how?


A is not empirical.
Reply 5
but how u know that? bcux someimes E.F = M.F
Original post by All rounder
but how u know that? bcux someimes E.F = M.F


empirical is the simplest whole number ratio.

C6H14 can still be divided through by two (C3H7 would be the empirical version of A)
You know when you give the answer with method but the OP is either illiterate or just dumb so they don't read
Original post by Lemauricien
You know when you give the answer with method but the OP is either illiterate or just dumb so they don't read


You haven't really though - they were confused because both A and D sum to 86, so putting D because the sum of mases is 86, which is what you did, doesn't resolve their issue, so there's not really any need to be nasty about it.
Original post by samb1234
You haven't really though - they were confused because both A and D sum to 86, so putting D because the sum of mases is 86, which is what you did, doesn't resolve their issue, so there's not really any need to be nasty about it.


The question says empirical so obvs it won't be A.... If you study properly you would never struggle with such a question.
Original post by Lemauricien
The question says empirical so obvs it won't be A.... If you study properly you would never struggle with such a question.


If you really want to go down that route, then by definition you should never struggle with any question at all, I mean after all they can only ask questions on what's in the spec right? This is the real world, people don't understand absolutely everything so if you're going to offer to help someone, actually help them to understand rather than just stating the answer and then when they ask for an explanation calling them 'dumb' and 'illiterate'. I'm sure you make mistakes just like everyone else, so there is no need to be like that when someone is asking for help.
Original post by samb1234
If you really want to go down that route, then by definition you should never struggle with any question at all, I mean after all they can only ask questions on what's in the spec right? This is the real world, people don't understand absolutely everything so if you're going to offer to help someone, actually help them to understand rather than just stating the answer and then when they ask for an explanation calling them 'dumb' and 'illiterate'. I'm sure you make mistakes just like everyone else, so there is no need to be like that when someone is asking for help.


Then they should have specified in the post that they couldn't understand why it isn't option A rather than leaving it for others to guess what they couldn't work out ; it would have been much more time efficient.....
Reply 12
Original post by Lemauricien
Then they should have specified in the post that they couldn't understand why it isn't option A rather than leaving it for others to guess what they couldn't work out ; it would have been much more time efficient.....


And it would have been much more 'time efficient' for you not to make such a derogatory comment.
Original post by Kozmo
And it would have been much more 'time efficient' for you not to make such a derogatory comment.


What did I say that was derogatory? That someone was not specific enough which consequently meant they had to wait longer to understand a concept?

Think about what you're saying before you make claims smh
Original post by Lemauricien
What did I say that was derogatory? That someone was not specific enough which consequently meant they had to wait longer to understand a concept?

Think about what you're saying before you make claims smh

You said that the op was dumb and illiterate. Anyway lets just move on
Does anyone know where to get the June 2015 OCR chemistry past papers F321, F322, F324 and F325??

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