Given a #60*"amu"# mass of carbon atoms, how many carbon atoms are there?

1 Answer
Apr 13, 2017

A #60*"amu"# mass of #""^12C# contains 5 carbon atoms........

Explanation:

A single #""^12C# atom contains 6 nuclear protons, and 6 neutrons, and to a first approx. this represents the mass of the atom. Five #""^12C# atoms should thus have a mass of #60*"amu"#.

This use of mass to express the number of atoms or the number of molecules, is enshrined by our use of #"Avogadro's number"#, and the idea of #"equivalent mass"#. This is one of the most important things you can learn as you study chemistry.

What is the actual mass of #6.022xx10^23# individual #""^12C# atoms; what about the mass of #6.022xx10^23# #""^13C# atoms?