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1. Hi guys, I worked out how to get 4 oxygens but just stuck on working out the number of carbons and hydrogens in the molecular formula of F. Can someone please help?

Attachment 730082730084
Ignore the fact that I put mass spectrometry in the title
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2. Bump
3. 54,2 % oxygen means there are four oxygen atoms as 118 x 54.2/100 = 64 = 4 oxygen atoms

The relative mass is 118 and subtracting your four oxygen atoms (64) from this leaves 54

Each carbon is 12 therefore 3 carbon atoms (36) would need 18 H atoms (clearly impossible)
5 carbon atoms = 60 units - also impossible

Therefore there are four carbon atoms (48) and 6 hydrogen atoms
4. (Original post by charco)
54,2 % oxygen means there are four oxygen atoms as 118 x 54.2/100 = 64 = 4 oxygen atoms

The relative mass is 118 and subtracting your four oxygen atoms (64) from this leaves 54

Each carbon is 12 therefore 3 carbon atoms (36) would need 18 H atoms (clearly impossible)
5 carbon atoms = 60 units - also impossible

Therefore there are four carbon atoms (48) and 6 hydrogen atoms
Thank you so much! But why is 3 carbon atoms and 18 hydrogens impossible? - 36 and 18 add up to 54 and there might be a structure that fit this?
5. (Original post by sienna2266)
Thank you so much! But why is 3 carbon atoms and 18 hydrogens impossible? - 36 and 18 add up to 54 and there might be a structure that fit this?
You're 'aving a laff!

Carbon has a maximum valency of 4 and hydrogen 1, the most hydrogen atoms possible for 3 carbon atoms is 8.
6. (Original post by charco)
You're 'aving a laff!

Carbon has a maximum valency of 4 and hydrogen 1, the most hydrogen atoms possible for 3 carbon atoms is 8.
Oh yeah! Lol sorry -blaming it on being tired

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