A carbon atom has a mass number of 12. How many protons and how many neutrons does it have?

1 Answer
Feb 1, 2016

The atom has #6# #"protons"#, and #6# #"neutrons"#.

Explanation:

You specified a carbon atom. By definition, the #C# atom has 6 protons, 6 positively charged nuclear particles, in its nucleus. You further specified the #""^12C# isotope. There must be 6 neutrons, 6 neutrally charged, massive particles in its nucleus.

If it's a carbon atom, the number of protons cannot change (why not?), but the number of neutrons in the nucleus can vary. #""^13C#, and #""^14C# isotopes are known. How many neutrons does each nuclide possess?