Why carbon-12 is an isotope of carbon?

1 Answer
anor277
Sep 8, 2015

Because elemental carbon has several isotopes. All carbon nuclei possess 6 protons, but some carbon nuclei possess more than 6 neutrons.

Explanation:

All carbon nuclei have the same atomic number, #Z#, the number of protons in the nucleus. For #C, Z = 6#, i.e. there are 6 protons in the carbon nucleus. If there were not 6 protons in the nucleus, the element would not be #C#. Most carbon nuclei have 6 neutrons; however, there are a very small percentage that have 7 or 8 neutrons, or even more neutrons. Approx. 99% of all carbon nuclei are carbon-12. It is the number of protons that determine the atomic number, that is the element's identity.

Related questions
See all questions in Isotopes
Impact of this question
5909 views around the world
You can reuse this answer
Creative Commons License