Explore zero, first, and second order kinetics. Compute rate constants, target times, and concentrations accurately. Compare temperature sensitivity using Arrhenius outputs, graphs, and exports.
Use consistent concentration, time, and rate constant units throughout the calculation.
The graph shows concentration decay across time using the active reaction order and effective rate constant.
Zero order: [A]t = [A]0 - kt
First order: ln([A]t) = ln([A]0) - kt, so [A]t = [A]0e-kt
Second order: 1/[A]t = 1/[A]0 + kt
Half-life: Zero: t1/2 = [A]0 / 2k, First: t1/2 = ln(2) / k, Second: t1/2 = 1 / (k[A]0)
Arrhenius relation: k = A e-Ea/RT
Temperature adjustment form: k(T) = kref × exp[(-Ea/R) × (1/T - 1/Tref)]
Two-temperature activation energy: Ea = R ln(k2/k1) / (1/T1 - 1/T2)
Select zero, first, or second order kinetics. The calculator changes the integrated rate law and half-life model automatically.
Provide initial concentration, optional target concentration, elapsed time, and either a direct rate constant or Arrhenius data.
Enter reference temperature, operating temperature, activation energy, and reference rate constant to estimate a new temperature-adjusted rate constant.
Supply k1, T1, k2, and T2 to estimate activation energy and the pre-exponential factor from two known measurements.
After calculation, the result table appears above the form. Download the results as CSV or PDF and review the trend graph below.
| Scenario | Order | [A]0 (mol/L) | k | Time (s) | [A]t Result (mol/L) |
|---|---|---|---|---|---|
| Surface decomposition | Zero | 0.90 | 0.020 | 15 | 0.60 |
| Radioactive-style decay model | First | 0.80 | 0.120 | 15 | 0.132 |
| Dimerization model | Second | 0.50 | 0.300 | 15 | 0.154 |
| Arrhenius correction sample | First | 1.00 | kref = 0.08 at 298 K | 20 | Depends on Ea and T |
The integrated rate law, half-life expression, concentration decay curve, and target-time calculation all change. The order determines how concentration influences reaction speed.
Yes. Use any units you prefer, but keep them consistent. If time is entered in minutes, your rate constant must also match minute-based kinetics.
A physical concentration cannot become negative. The calculator clips zero-order decay at zero to prevent impossible negative values in the result and graph.
It adjusts the rate constant for a new temperature using activation energy, a reference temperature, and a known reference rate constant.
Enter a target concentration when you want the time needed to reach a chosen conversion level, endpoint, or allowable concentration threshold.
Yes. Enter k1, T1, k2, and T2. The calculator uses the two-temperature Arrhenius form to estimate activation energy and the pre-exponential factor.
For second-order kinetics, the half-life formula contains the starting concentration. That means the half-life changes when the initial concentration changes.
No. It is excellent for fast estimates, teaching, and screening. Detailed laboratory fitting may still need regression, error analysis, and mechanism validation.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.