Molecular Weight for nucleotides


by mountain
Tags: molecular, nucleotides, weight
mountain
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#1
Apr12-05, 03:12 PM
P: 53
When it says; "Molecular Weight: daltons (g/M)" What does daltons mean and what does (g/M) stand for? Does g/M stand for g/mol or what?

How can they calculate Molecular Weight for nucleotides?


Thanks for any inputs.
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Monique
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#2
Apr12-05, 03:19 PM
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A dalton is an atomic mass. For instance C12 has a mass of 12.0000 Da. The mw is the mass of 1 mole of a particular molecule. By definition 1 mole of carbon atoms weighs 12 grams.
mountain
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#3
Apr12-05, 03:53 PM
P: 53
Thanks.

But what does M stand for in g/M?

Moonbear
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Apr12-05, 04:07 PM
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Molecular Weight for nucleotides


Quote Quote by mountain
Thanks.

But what does M stand for in g/M?
You had it right...mole.
gerben
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#5
Apr13-05, 01:34 AM
P: 540
Quote Quote by Monique
A dalton is an atomic mass. For instance C12 has a mass of 12.0000 Da. The mw is the mass of 1 mole of a particular molecule. By definition 1 mole of carbon atoms weighs 12 grams.
(why only four zeros?)

(1) C12 has a mass of 12 Da (by definition; exactly 12, there is no uncertainty)
(2) a mol of C12 atoms weighs 12 grams (by definition)

From (1) and (2) it follows that a dalton is the number of grams that go into a mol (gram/mol)
__________________________________________________
(1) C12 = 12 Da <--> mol C12 = mol 12 Da
(2) mol C12 = 12 gram
(substitute 2 into 1) 12 gram = mol 12 Da <--> gram/mol = Da
kalladin
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#6
Apr13-05, 09:00 AM
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doesn't g/M mean g/mol/L?
cronxeh
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#7
Apr13-05, 10:11 AM
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its not exactly 12, and its not exactly 16 for oxygen either

but they decided to make it 12 anywho. so just use 12 as a whole number

6 protons = 6 x 1.007277 6.043662
6 neutrons = 6 x 1.008665 6.051990
6 electrons = 6 x 0.000548 0.003288
Total 12.098940
Monique
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#8
Apr13-05, 11:07 AM
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Carbon was easy to purify, that is why they used it as a reference and why it is the whole number 12.


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