Electronvolts to kJ/mol Converter
Common Conversions
| eV/particle | kJ/mol |
|---|---|
| 0.01 | 0.965 |
| 0.025 | 2.412 |
| 0.1 | 9.649 |
| 0.5 | 48.243 |
| 1 | 96.485 |
| 2 | 192.97 |
| 3 | 289.456 |
| 5 | 482.426 |
| 10 | 964.853 |
| 13.6 | 1312.2 |
| 100 | 9648.53 |
Why this conversion matters in chemistry
DFT output drops energies in eV or hartree per particle; downstream thermochemistry runs in kJ/mol. A 0.5 eV per-particle reaction energy becomes 48.24 kJ/mol — the form a microkinetic model accepts as input. The multiplier of 96.485 kJ/mol per eV is the Faraday constant divided by 1000, and falls out of Avogadro's number × the elementary charge. It comes up when computational energetics meet experimental thermochemistry — the same identity that links any per-particle electron-energy quantity to its molar form.
Formula
Where the factor comes from
The number 96485 turns up twice in a chemist's working life, and it is the same number both times. Multiply the elementary charge by Avogadro's number — 1.602176634 × 10⁻¹⁹ C × 6.02214076 × 10²³ mol⁻¹, both fixed exactly by the 2019 SI revision — and the product is 96485.3321233100184, with no rounding anywhere in it. Label that coulombs per mole and it is the Faraday constant used in electrolysis stoichiometry. Label it joules per mole per volt and it is this conversion, because one electronvolt is one elementary charge carried through one volt. Divide by 1000 for the kilo and the factor is 96.4853321233100184 kJ/mol per eV. The chemistry differs; the arithmetic is a single product.
Precision and significant figures
Write 96.485 and you have already outrun any realistic input. The factor's exactness means it never limits an answer, so the honest precision of a converted value is the precision of the eV that went in — and eV numbers from electronic-structure output or from a fitted absorption edge seldom deserve more than three. Rounding to 96.5 costs 0.015 percent, comfortably inside the noise of any comparison you would draw from the result. Where digits do earn their keep is electrochemistry: a cell potential measured to a millivolt against a stable reference supports four figures in the converted ΔG, and there the full 96.4853 belongs.
Worked Examples
The conversion anchor — a useful mental factor for any computational versus experimental cross-check.
kT at room temperature — the per-mole thermal-energy floor.
A typical strong-bond dissociation energy — about the C–H bond in methane.
Hydrogen's ionization energy expressed per mole — the calibration anchor for atomic energetics.
Common mistakes
96485 and 96.485 are a thousand apart
The Faraday constant is 96485 C/mol; this conversion factor is 96.485 kJ/mol per eV. Same digits, different prefix, and both appear inside the same electrochemistry calculation. A ΔG emerging as 237,000 kJ/mol rather than 237 has taken the C/mol form into a kJ expression. Keep the unit label attached to the constant instead of trusting the memory of the digits.
Electrons transferred is not always one
The factor converts one electronvolt per particle. A redox couple moving n electrons obeys ΔG = −nFE, so a two-electron process at 1.23 V gives a ΔG of −237 kJ/mol, not −119. Band gaps and orbital energies are per-electron quantities and pass through cleanly; anything drawn from a balanced half-reaction has to bring its n along with it.
Hartree and rydberg also come out of DFT
Electronic-structure packages report in whatever their internal units happen to be: one hartree is 27.2114 eV or 2625.5 kJ/mol, and one rydberg is half a hartree at 13.6057 eV. Applying 96.485 to a hartree number understates the energy by a factor of 27. Read the output header before the multiplier, especially when comparing two codes that default differently.