Find the simplest C/H/O/N formula from grams of each element, or from percents treated as grams.
| Empirical formula | – |
Use this calculator with combustion or CHN data when you have masses of C, H, O, and N and need the empirical formula before hunting for a molecular one.
Each mass is divided by the atomic mass (C 12.011, H 1.008, O 15.999, N 14.007), then all mole counts are divided by the smallest. Percents work if you treat the sample as 100 g. Only C, H, O, and N are accepted. Subscripts are rounded toward nearby simple ratios; this is a classroom reduction, not a high-precision fit.
Do not use a mass-unit selector here: grams and mass percents must stay numerical as entered so that 40 meaning 40% is not converted as if it were 40 g.
Mass C: Grams of carbon, or percent C treated as grams. 0 if none.
Mass H: Grams (or %) of hydrogen. 0 if none.
Mass O: Grams (or %) of oxygen. 0 if none.
Mass N: Grams (or %) of nitrogen. 0 if none.
Empirical formula: Simplest whole-number formula from those mole ratios.
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