Second-order Integrated Rate Law Calculator
🔋 Rates & Electrochemistry. Use the Second-order integrated rate law formula to find [a] at time t, starting [a]₀, rate constant k, time: pick the value you want, type the others, and the answer updates as you go.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| [A] at time t | mol/L |
| Starting [A]₀ | mol/L |
| Rate constant k | L/mol/s |
| Time | s |
Worked example
Find the [a] at time t when Starting [A]₀ = 0.1 mol/L, Rate constant k = 0.2 L/mol/s, Time = 100 s.
Using 1/[A] = 1/[A]0 + kt: [A] at time t = 0.033333 mol/L.
Frequently asked questions
What is the formula for Second-order integrated rate law?
1/[A] = 1/[A]0 + kt.
What do the letters stand for, and what units are used?
[A] at time t in mol/L, Starting [A]₀ in mol/L, Rate constant k in L/mol/s, Time in s.
How do you calculate [a] at time t?
Put the values into 1/[A] = 1/[A]0 + kt. For example, with Starting [A]₀ = 0.1 mol/L, Rate constant k = 0.2 L/mol/s, Time = 100 s, [a] at time t = 0.033333 mol/L.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value ([a] at time t, starting [a]₀, rate constant k, time) and fill in the others: it rearranges the formula for you.
