Molar concentrations and volume calculations in NMR tubes

We recently had a student ask us about molar concentrations and volume calculations in NMR tubes, so we thought that the following example could possibly help out other students having similar problems. In the original question, the student asked for the molar and mass concentrations of a 25k Daulton protein, of which 2.5 mg were dissolved in 1 liter of water. We wrote the solution out in pen, because it was easier to read. Click the link below to view.

http://www.nmrtubes.com/blog/121506_formula.jpg