How do you caclulate the gram atomic mass?

Atomic mass of oxygen is 15.9994. The fun is, we simply say the atomic mass or weight of atom or molecule with some numerals. The following unit is not gram or kilogram. That one is in a.m.u. a.m.u...

gram atomic mass (or atomic mass) of nitrogen (N) is 14 u.

32.065

Is the atomic mass of an element (Co, Ni, Hg, Etc) expressed in grams. Take the atomic mass (little number under the Chemical symbol) and round the number off to one place after the decimal point to...

Tricky bit that, but it's part of the definition of the molar mass. Basically, if you were to collect 6.022×1023 atoms of a substance of a particular atomic mass (lets say 6 for arguments sake),...