Molar Flow Rate converter
Moles delivered per unit time, the natural flow unit for reaction and separation calculations.
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tap to loadOne kilomole per hour in every molar flow rate unit
6 rows| Unit | Symbol | 1 kmol/h equals |
|---|---|---|
| Mole per second | mol/s | 0.2777777778 |
| Mole per minute | mol/min | 16.66666667 |
| Mole per hour | mol/h | 1,000 |
| Millimole per second | mmol/s | 277.7777778 |
| Micromole per second | µmol/s | 277,777.7778 |
| Kilomole per second | kmol/s | 0.0002777777778 |
How the kilomole per hour to mole per second conversion works
This converter treats mole per second (mol/s) as the base unit, since it is the SI-coherent way to express molar flow. Every other unit here is just mol/s rescaled by a time factor: mole per minute is 1/60 of that rate, mole per hour is 1/3600, and millimole or micromole per second shrink the amount side by a thousand or a million. Kilomole per second and kilomole per hour do the opposite, scaling the amount up by a thousand.
The site's featured pair is kilomole per hour to mole per second. Because 1 kmol/h equals 1000 mol over 3600 seconds, the factor works out to 0.2777777778, and the formula is mol/s = kmol/h × 0.2777777778. Going back the other way, you multiply by 3.6, which is exactly 1 ÷ 0.2777777778.
Take a reactor fed at 10 kmol/h of a gas reagent: 10 × 0.2777777778 = 2.777777778 mol/s, a number you would plug directly into a rate-law calculation written in SI units. For a larger plant stream running at 500 kmol/h, the same multiplication gives 500 × 0.2777777778 = 138.8888889 mol/s.
Molar flow rate matters wherever chemistry, not just mass, drives the outcome. In reaction engineering, rate laws are written per mole, so a CSTR or plug-flow reactor design lives or dies on knowing mol/s of each reagent entering and leaving. Catalysis researchers report turnover frequency against moles of feed gas per second, fermentation engineers track substrate and CO2 evolution in mmol/s or mol/h, and process engineers on a distillation or absorption column size equipment around kmol/h flows straight off the P&ID.
The most common slip is treating molar flow as if it were mass flow. A mol/s figure says nothing about kilograms per second until you multiply by the molecular weight of whatever is flowing — 1 mol/s of hydrogen is about 2 grams per second, while 1 mol/s of a heavy hydrocarbon can be hundreds of grams per second. It is also easy to misplace a decimal between kmol/h (common on industrial data sheets) and mol/s (the SI default in textbooks), since the two differ by a factor of exactly 3.6, not a round power of ten.
Questions
How many mole per second are in one kilomole per hour?
One kilomole per hour equals 0.2777777778 mol/s, since 1000 mol divided by 3600 seconds gives that rate.
Which units does this molar flow rate converter cover?
Seven units referenced to mole per second: mole per second, mole per minute, mole per hour, millimole per second, micromole per second, kilomole per second, and kilomole per hour.
How much rounding happens in these molar flow conversions?
Most pairs here are exact powers of ten (mol/s to mmol/s, for example), but anything crossing the hour-to-second boundary, like kmol/h to mol/s, involves a repeating decimal (1/3.6), so results are rounded to about ten significant figures rather than being perfectly clean.
When would I use mol/s instead of kmol/h?
Mol/s and mmol/s are the natural scale for lab-bench and kinetics work, where reagent amounts are small and rate equations are written in SI units; kmol/h is the convention on industrial process flow diagrams, where plant-scale streams are more conveniently expressed as thousands of moles per hour.
Is molar flow rate the same thing as mass flow rate?
No. Molar flow rate counts particles (moles) per unit time, while mass flow rate counts kilograms per unit time; converting between them requires multiplying or dividing by the molecular weight of the specific substance flowing, which this converter does not assume.
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