A-level Chemistry Revision Squad!

Help with MAss spectrum



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There will be another peak for Chlorine-37 (+), like the already plotted Chlorine-35 (+) one.

The x-axis represents mass/charge or m/e ratio - I.e. Mass divided by charge.

So there will be another peak for 35/2(+) = 17.5

And another at 37/2(+) = 18.5

(Also y-axis represents relative abundance - for example could be written as a percentage)

There is no real way of knowing from the information given what the abundance of Cl (+) is compared to Cl (2+) however you would expect there to be much less of the 2+ ions

Thank you, yes I would do what u do. But
The mark scheme says if there's four peaks, you lose a mark




Posted from TSR Mobile

If more than 3 peaks drawn, so if you were to draw 4 then yes I think you'd lose that mark, but 4 in total including the peak already provided is alright I assume

I was looking for a Chemistry Revision Thread but there were not any so I decided to make one

Feel free to ask questions regardless of your exam board (because chemistry is chesmitry), and we'll all be happy to answer
hey question here........
Compound X changes the colour of warm acidified sodium dichromate(VI) from orange to green.
1 mol of X reacts with 2mol of HCN in the presence of KCN.
What could X be?
A)CH3CH2CH2CHO
B)CH3COCH2COCH3
C)H2C=CHCH2CHO
D)OHCCH2CH2CHO

A branched Alkene A was reduced with Hydrogen to form a compound B. Compound B had a composition by mass of C:82.8%, H:17.2% (Mr=58).

Compound A was reacted with steam with an acid catalyst to produce a mixture of two structural isomers C and D .

a)Calculate the empirical and molecular formula of a compound B?

I'd like some advice as to where to start trying to work out how to tackle this question.

any help is greatly appreciated .

kind regards to anyone who is helping me

Work out the empirical formula of B.
Then work out the Mr of the empirical formula. If it doesn't match the Mr of 58, it isn't the molecular formula as well. So, multiply the empirical formula's Mr to get the Mr of 58.

You know how to do the empirical formula right?

Sorry my friend I dont this is the part I'm struggling with . if you could point me in the correct direction I'd be greatly appreciative .

thanks

Here is a method for the question that I made, with explanations. (Here is a BBC bitesize explanation - http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa_pre_2011/chemcalc/chemcalc_higherrev2.shtml )