The molar mass of urea (CH4N2O) is 60.056 g/mol.
Case matters: CO is carbon monoxide, Co is
cobalt. Brackets and hydrates are fine — try
or
.
| Element | Atoms | Atomic mass | Mass contributed | Percent |
|---|---|---|---|---|
| Carbon (C) | 1 | 12.011 | 12.011 | 20.00% |
| Hydrogen (H) | 4 | 1.0080 | 4.032 | 6.71% |
| Nitrogen (N) | 2 | 14.007 | 28.014 | 46.65% |
| Oxygen (O) | 1 | 15.999 | 15.999 | 26.64% |
| Total | 8 | 60.056 | 100.00% |
12.011 + 4.032 + 28.014 + 15.999 = 60.056 g/mol
Grams and moles
25 g of urea is 0.4163 mol, because 25 ÷ 60.056 = 0.4163.
These elements have no single atomic weight. Their isotopic mix varies slightly depending on where on Earth the sample came from, so the figure used here is the conventional value IUPAC publishes for when one number is needed: carbon is 12.011, and really lies between 12.0096 and 12.0116; hydrogen is 1.0080, and really lies between 1.00784 and 1.00811; nitrogen is 14.007, and really lies between 14.00643 and 14.00728; oxygen is 15.999, and really lies between 15.99903 and 15.99977.
Urea is 60.056 g/mol and it is 46.65% nitrogen, the highest nitrogen fraction of any solid fertiliser in common use. That single figure is why it accounts for more than half of world fertiliser nitrogen: shipping a tonne of urea moves 466 kilograms of nitrogen, against 350 for ammonium nitrate.
It also has a place in the history of the subject. Friedrich Wohler made it from ammonium cyanate in 1828, producing an unmistakably organic substance from unmistakably mineral starting materials. Ammonium cyanate has the identical formula, so the reaction is an isomerisation and both sides of it weigh 60.056 g/mol. Nothing entered or left; the atoms simply rearranged, and the idea that living things ran on a separate chemistry did not survive it.
Your kidneys produce around 30 grams of it a day, roughly half a mole, as the way the body disposes of excess nitrogen from protein.
Acetic acid at 60.052 g/mol is four thousandths away and shares nothing else with it.