Science & Environment
Reaction Half-Life Calculator
Calculate the half-life of a chemical reaction for zero-order, first-order, or second-order kinetics.
Your inputs
Change any value to update the result instantly.
Half-life
13.8629 time units
Reaction order
1
Rate constant
0.05
Initial concentration
1 mol/L
Formula and working
Zero: t½=[A]0/(2k); First: t½=ln2/k; Second: t½=1/(k[A]0)
- 1
Collect the inputs
Rate constant k = 0.05; Initial concentration [A]0 = 1 mol/L; Reaction order = 1
- 2
Apply the formula
Zero: t½=[A]0/(2k); First: t½=ln2/k; Second: t½=1/(k[A]0)
- 3
Result
Half-life = 13.8629 time units
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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