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carbon-13

Structure via PubChem · Public domain (PubChem)

EntityQ1770822· pop 25· linked from 228 articles

Also known as C-13, 13C, carbon-13 atom, (13)C, (13)6C, ¹³C

Carbon-13 (13C) is a natural, stable isotope of carbon with a nucleus containing six protons and seven neutrons. It constitutes about 1.07% of natural carbon and is one of the so-called environmental isotopes.

Key facts

Isotope.symbol
C
Isotope.mass_number
13
Isotope.mass
13.003354835
Isotope.num_neutrons
7
Isotope.num_protons
6
Isotope.abundance
1.07%
Isotope.image
Carbon-13.svg
Isotope.spin

via Wikipedia infobox

Chemical data

Formula
C
Molecular weight
13.003354835 g/mol
IUPAC name
carbane
SMILES
[13C]
InChIKey
OKTJSMMVPCPJKN-OUBTZVSYSA-N
XLogP
0.6
Polar surface area
0 Ų
H-bond donors
0
H-bond acceptors
0
Formal charge
0

via PubChem

~5 min read

Encyclopedic overview

5 sections
Contents
  • Detection by mass spectrometry
  • Uses in science
  • Production
  • See also
  • Notes

Carbon-13 (13C) is a natural, stable isotope of carbon with a nucleus containing six protons and seven neutrons. It constitutes about 1.07% of natural carbon and is one of the so-called environmental isotopes.

== Detection by mass spectrometry == A mass spectrum of an organic compound will usually contain a small peak of one mass unit greater than the apparent molecular ion peak (M) of the whole molecule. This is known as the M+1 peak and comes from the few molecules that contain a 13C atom in place of a 12C. A molecule containing one carbon atom will be expected to have an M+1 peak of approximately 1.1% of the size of the M peak, as 1.1% of the molecules will have a 13C rather than a 12C. Similarly, a molecule containing two carbon atoms will be expected to have an M+1 peak of approximately 2.2% of the size of the M peak, as there is double the previous likelihood that any molecule will contain a 13C atom.

Excerpted from Wikipedia’s “carbon-13” article, available under the CC BY-SA 4.0 licence.