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AbdalAziz
I dont know

Oxygen is DIatomic.
Reply 21
addylad
Oxygen is DIatomic.


OK i just googled diatomic, and it means it has 2 atoms, but how do i work that out.

How many atoms are there in carbon? Is there a specific formula i can use to get the answer?
AbdalAziz
OK i just googled diatomic, and it means it has 2 atoms, but how do i work that out.

How many atoms are there in carbon? Is there a specific formula i can use to get the answer?

Carbon is C, the question you're asking is 'how long is a piece of string?' You could say, 'how many carbon atoms in 24g?' That question could be answered.
Reply 23
addylad
Carbon is C, the question you're asking is 'how long is a piece of string?' You could say, 'how many carbon atoms in 24g?' That question could be answered.


Yes please answer
AbdalAziz
Yes please answer

moles is grams/RAMs, so 16g/32 is 0.5. There are 0.5 moles of oxygen in 16g. There are 0.5 x 6 x 10^23 = 3 x 10^23 atoms in half a mole (16g), so double it and you get back to 6 x 10^23 atoms of oxygen. Hope this makes sense, chances are I am wrong though. :p:
Reply 25
the Mr is the weight of one mole of that substance in grams.

n=mass/Mr
Mass of substance (grams) divided by mass number of atom/molecule and then times this value by 6.022x10^23
Reply 27
OK one last question, with workings

How many atoms are there present in 12g of Carbon?

Is it you work out the number of moles first: so 12/12 = a mole.

then 1 * 6.022*10^23?
Reply 28
as the Mr of carbon is 12, There are 6.022*10^23 atoms in 12 grams = 1 mole
Mr = mass of one mole in gr
Reply 29
jaydakiss
as the Mr of carbon is 12, There are 6.022*10^23 atoms in 12 grams = 1 mole
Mr = mass of one mole in gr


and for oxygen, there is 6.022*10^23 atoms in 16 grams and 1 mole?
Reply 30
AbdalAziz
and for oxygen, there is 6.022*10^23 atoms in 16 grams and 1 mole?

yep :smile:
Reply 31
but 1 mole of 02 (diatomic molecule) would have twice the Mr, 32 therefore weighing 32g
Reply 32
jaydakiss
yep :smile:


Really?

I thought there'd be 6.02 x 1023 molecules of O2.

If you think about it, one mole of ammonia is surely 6.02 x 1023 molecules of NH3, so one mole of oxygen would be the above, no?
Reply 33
Kinkerz
Really?

I thought there'd be 6.02 x 1023 molecules of O2.

If you think about it, one mole of ammonia is surely 6.02 x 1023 molecules of NH3, so one mole of oxygen would be the above, no?


yes but he specifically said 16g, which is one mole of O or half a mole of O2
Reply 34
jaydakiss
yes but he specifically said 16g, which is one mole of O or half a mole of O2


Right, yes, I see.

Had to think about that for a minute.