Acids, equilibrium & kinetics · HL
Rate Order from Two Experiments Calculator (HL)
HL tool. This two-trial relation assumes other reactant concentrations and conditions are unchanged.
Your values
Start with the example or enter your own values. Use a dot for decimals and e for scientific notation.
Calculated locally. No account or input upload.
Result & working
ExampleThe calculator is loading. The worked example is also shown below.
Step-by-step working
The formula
r₂/r₁ = (c₂/c₁)ⁿ
n = ln(r₂/r₁)/ln(c₂/c₁)
k = r/cⁿ (for this one-variable form)
| Symbol | Meaning |
|---|---|
| n | Order with respect to the changing reactant. |
When to use this calculator
The order obtained from experimental data need not equal a stoichiometric coefficient. For a multivariable rate law, isolate one reactant at a time with the others effectively constant.
Worked example
The page opens with these example values. The result below is pre-generated for reference.
- r₂/r₁ = 0.08/0.02 = 4
- c₂/c₁ = 0.2/0.1 = 2
- n = ln(r₂/r₁)/ln(c₂/c₁) = 2
- k = r₁/c₁ⁿ = 0.02 / (0.1)^(2) = 2
order n = 2
Common mistakes
- If c₂/c₁ = 1, the two trials cannot determine this order.