# Why is the relative atomic mass of Chlorine is 35.5Watch

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#1
Yeah, I don't get why.

I've tried searching but I need help.
0
3 years ago
#2
The average mass is 35.5, about half of chlorine atoms have a RAM of 35, the other half 36, same with every other decimal one.
1
3 years ago
#3
Thank the lord
0
3 years ago
#4
Thank the lord
ooPS I DIDN'T FNISH THE POST
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3 years ago
#5
Oh god my reply is a trainwreck
0
3 years ago
#6
What i meant to say was thank the lord my revision could help me qith this question. Basically the value is an average o all the isotopes taking into account the relative abundance
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#7
Thanks!

Good luck to all tomorrow
1
3 years ago
#8
If a element has more than one isotope the relative atomic mass takes account of the relative abundance and RAM mass of each isotope, for chlorine (I think) about 3/4 is Cl-35 and about 1/4 is Cl-37, giving 35.5 overall, though I very much doubt this is necessary to know. The values will be different for each atom obviously, but that is the general idea.
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3 years ago
#9
(Original post by Jammy Duel)
The average mass is 35.5, about half of chlorine atoms have a RAM of 35, the other half 36, same with every other decimal one.
That's incorrect mate :/
There are two isotopes of Chlorine. Cl-35 and Cl-37. On average 75% of the atoms are Cl-35 and 25% are Cl-37. Therefore on average the atomic number is 35.5.
35+35+35+37 = 142
142 / 4 = 35.5
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3 years ago
#10
(Original post by Jono-Wolf)
That's incorrect mate :/
There are two isotopes of Chlorine. Cl-35 and Cl-37. On average 75% of the atoms are Cl-35 and 25% are Cl-37. Therefore on average the atomic number is 35.5.
35+35+35+37 = 142
142 / 4 = 35.5
It's been a while (5 to be precise) but the general point is correct

Posted from TSR Mobile
0
3 years ago
#11
That is the average weighted mass of an atom of chlorine compared to 1/12th the mass of an atom of carbon-12
Spoiler:
Show
My Chem Teacher should be proud I remembered that
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