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# Why do scientists always say 'relative atomic mass' when talking about a.... watch

1. (Original post by morecambebay)
The exact weight of carbon is 12 point something. when you take this 12 point something and divide it by 12 to get a comparison amount...that amount will fit into 12 point something exactly 12 times.
2. (Original post by Craig_D)
Well, 12 = 6 protons + 6 neutrons Rather than the usual 8 neutrons to 6 protons.
3. (Original post by charco)
Don' worry. the OP just needs to get things a little clearer in his/her mind..
People on here are confusing me. Okay back to square 1.

why doesn't the relative atomic mass have a units..
4. (Original post by charco)
another looney ..
I'm not a 'looney' [sic] You're not making it clear what you're suggesting, and neither is the OP. It may be the fact that I've been awake 32 hours, but nobody seems to know what anyone else is on about.
5. (Original post by Miss Understood)
People on here are confusing me. Okay back to square 1.

why doesn't the relative atomic mass have a units..
Nothing relative has units.

If somebody asked you how much heavier you are than a frog you might say 105 times heavier ....

.. but no units
6. (Original post by Miss Understood)
People on here are confusing me. Okay back to square 1.

why doesn't the relative atomic mass have a units..
It is a ratio.
7. (Original post by Craig_D)
I'm not a 'looney' [sic] You're not making it clear what you're suggesting, and neither is the OP. It may be the fact that I've been awake 32 hours, but nobody seems to know what anyone else is on about.
go to sleep .... it's good for you
8. (Original post by morecambebay)
Did I not write that in the bit you quoted?
If you mean this bit:

Hold on, the relative atomic mass will be exactly 12 because if you divide the exact number by 12 (to get the comparison) then see how many times it fits into the origonal, you will get 12. The actual mass isnt though.
You were bumbling so much it made no sense to me. Also in the first bit you explicitly said:

Everyone like who? it isnt exact, it is just the one whose decimal causes the least trouble.
Which suggests exactly the opposite.

So no, you didn't.

EDIT the first: Yes, thanks for the neg for correcting you, I would neg you but apparently I need to rate someone else before I do. Although I don't actually remember when I negged you, it wasn't this thread. Apparently you got something wrong elsewhere that I took offence too.
9. (Original post by charco)
Nothing relative has units.

If somebody asked you how much heavier you are than a frog you might say 105 times heavier ....

.. but no units
what is a relative atomic mass?
10. Well if a mass of a proton is 1.6726...x10^-28 kg which is a very small. And a proton and neutron have similar masses and when compared to a mass of a proton which is close to zero.
ie.protonelectron = 10 i think we can all agree that it would be a lot simpler working out calculations and be a lot more accurate if we use relative masses.
11. (Original post by Concept186)
If you mean this bit:

You were bumbling so much it made no sense to me.
Learn to read then. Maybe if you actually understood what you are talking about instead of parroting off text book phrases you would have got it.
12. (Original post by Concept186)
If you mean this bit:

You were bumbling so much it made no sense to me. Also in the first bit you explicitly said:

Which suggests exactly the opposite.

So no, you didn't.
The atomic weight isnt exactly 12 . The relative is.
13. (Original post by charco)
go to sleep .... it's good for you
Particularly patronising individual, aren't you? Suggestive of a latent feeling of inferiority.
14. (Original post by Miss Understood)
what is a relative atomic mass?
The mass compared to a carbon 12 isotope (which has an internationally agreed mass of 12 .0000000000 atomic mass units)
15. (Original post by morecambebay)
The atomic weight isnt exactly 12 . The relative is.
this whole thread is about relative so what does atomic have to do with anything!?

I am still confused about what the actual question is.
16. (Original post by morecambebay)
Learn to read then. Maybe if you actually understood what you are talking about instead of parroting off text book phrases you would have got it.
So.. you said something bumbling and confusing, something else specifically contradicting what I said, then claim to have said what I said and insult me for no good reason?

Yeah, **** right off.

Admittedly I haven't done chemistry since I finished my A-levels a couple of years ago, but I'm not sure how correcting or at the very least clarifying what you said with a bit of totally correct science that I do actually understand is "parroting out of a text book" or shows that I don't understand what I'm talking about. I'm not an amazing chemist, barely scraped an A and that was two years ago, but basic GCSE **** like this I can still manage just fine.
17. (Original post by Craig_D)
Particularly patronising individual, aren't you? Suggestive of a latent feeling of inferiority.
Damn .. you've sussed me out

18. (Original post by charco)
The mass compared to a carbon 12 isotope (which has an internationally agreed mass of 12 .0000000000 atomic mass units)
no.
http://www.chemicalelements.com/elements/c.html
19. (Original post by charco)
Damn .. you've sussed me out

Pleasant to debate with you
20. Thats the relative mass which takes into account the small amount (~1/100) of carbon-13 and other isotopes.

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