For students learn about radioactive decay mean lifetime and the definition and formula derivation of the relationship between half life constants and the Half-Life Calculator is a crucial tool in physics and chemistry.

Half-Life Calculator

Half-Life Calculator

Calculate radioactive decay over time using the exponential decay formula. Determine remaining amounts, decay times, and half-life periods.

N(t) = N₀ × (1/2)^(t/t₁/₂)

Where N(t) = remaining amount, N₀ = initial amount, t = time elapsed, t₁/₂ = half-life

Decay Calculator

Reverse Calculator

Common Radioactive Isotopes

Click on an isotope to use its half-life in calculations

Carbon-14
5,730 years
Used in radiocarbon dating
Uranium-238
4.47 billion years
Nuclear fuel, geological dating
Plutonium-239
24,110 years
Nuclear weapons, reactors
Cesium-137
30.17 years
Nuclear fission byproduct
Iodine-131
8.02 days
Medical treatments, nuclear accidents
Radon-222
3.82 days
Indoor air pollution, lung cancer risk

Decay Visualization

Perform a calculation to see the decay curve

Calculation History

No calculations yet

Half-Life Calculator

To determine how long it takes for a drug to decompose to half of its initial amount and a half-life calculator is frequently employed. It becomes crucial in nuclear physics when examining unstable isotopes. Additionally it is used in environmental investigations as well as chemistry and pharmacology. It is possible to make extremely accurate forecasts regarding the decay process by using a half-life calculator. This guarantees accuracy in intricate computations while simultaneously saving time.

Also because it defines the stability of elements and the idea of half-life is essential. Scientists and students can use this calculator to quickly determine findings and prevent human errors.

A black handheld scientific half-life calculator displaying isotope 60 with a time of 8 hours, a decay constant of 0.0231 per hour, and a calculated half-life of 30 hours on the screen.

Define Formula

 Half-life (t₁/₂): The time required for the concentration of a reactant to decrease to half of its initial concentration.

Rate constant (k): A proportionality constant in the rate law that relates the rate of reaction to the concentration of reactants.

The relationship between half-life and rate constant depends on the order of the reaction.

🧮 Derivation of Formulae

First-order reaction

Rate law:

$$

\frac{d[A]}{dt} = -k[A]

$$

Integrating:

$$

[A] = [A]_0 e^{-kt}

$$

At half-life, $[A] = \frac{[A]_0}{2}$:

$$

\frac{[A]0}{2} = [A]_0 e^{-k t{1/2}}

$$

Dividing by $[A]_0$:

$$

\frac{1}{2} = e^{-k t_{1/2}}

$$

Taking natural log:

$$

\ln \left(\frac{1}{2}\right) = -k t_{1/2}

$$

$$

t_{1/2} = \frac{\ln 2}{k}

$$

✅ For first-order, half-life is constant and independent of concentration.

Second-order reaction

Rate law:

$$

\frac{d[A]}{dt} = -k[A]^2

$$

Integrated form:

$$

\frac{1}{[A]} = \frac{1}{[A]_0} + kt

$$

At half-life, $[A] = \frac{[A]_0}{2}$:

$$

\frac{1}{[A]0/2} = \frac{1}{[A]_0} + k t{1/2}

$$

$$

\frac{2}{[A]0} = \frac{1}{[A]_0} + k t{1/2}

$$

$$

t_{1/2} = \frac{1}{k [A]_0}

$$

✅ For second-order, half-life depends on the initial concentration.

 Zero-order reaction

Rate law:

$$

\frac{d[A]}{dt} = -k

$$

Integrated form:

$$

[A] = [A]_0 – kt

$$

At half-life, $[A] = \frac{[A]_0}{2}$:

$$

\frac{[A]0}{2} = [A]_0 – k t{1/2}

$$

$$

k t_{1/2} = \frac{[A]_0}{2}

$$

$$

t_{1/2} = \frac{[A]_0}{2k}

$$

✅ For zero-order, half-life decreases as concentration decreases.

Half Life

The time it takes for a radioactive material to decay to 50% of its initial value is known as its half-life. For instance just half of the initial atoms will be left in a substance with a half-life of ten years. Only a fraction is left after another ten years.

How long a drug is active in the body is determined by its half-life in medicine. Studying the characteristics of unstable isotopes is beneficial in physics. Therefore the half life provides a comprehensive grasp of the processes of decline both natural and man-made.

Mean Lifetime

Another important concept in research on radioactive decay is the mean lifetime. The mean lifetime is the average amount of time until a nucleus decays while half-life concentrates on the period for 50% reduction. Although the mean lifetime is mathematically longer than the half-life there is a constant factor that connects the two.

The mean duration offers a more profound insight into atom stability in radioactive processes. Despite their differences both numbers are necessary for correctly assessing decay rates. It is possible to express decay forecasts in terms of probability by knowing the mean lifetime. 

Definition and Formula Derivation of the Relationship Between Half Life Constants

Accuracy in science depends on the definition and formula derivation of the link between half life constants. The mathematical relationship between the decay constant (λ) and half-life (T½) is as follows:

T2 = ln(2) / λ

The decline constant denoted by λ is the likelihood of a nucleus decaying per unit of time. The relationship between half-life and mean duration is also demonstrated by the definition and formula derivation of the relationship between half-life constants. The average lifespan is determined by:

τ = 1 / λ

Together these result in the following conclusion:

τ = T½ / ln(2)

Decline probability or mean lifespan and half-life are thus properly connected by the definition and formula derivation of the link between half-life constants. 

“Minimalist digital Half-Life Calculator interface showing half-life input of 24, an initial amount of 100, and a calculated remaining amount of 6.25 with a blue calculate button.

Applications of Half-Life Calculator

There are real-world uses for the Half-Life Calculator outside of nuclear physics. It aids medical professionals in understanding the duration of pharmacological activity. It helps determine the age of remains in archaeology by using radiocarbon dating. The Half-Life Calculator is a tool used by environmentalists to forecast how long pollutants will persist in the environment.

The Half-Life Calculator also becomes a universal scientific instrument because it may be used in a variety of domains. As a result it gives experts and students alike a trustworthy way to calculate.

Conclusion

In conclusion a comprehensive understanding of radioactive decay may be formed by combining the Half-Life Calculator or half life or mean lifetime and the definition and formula derivation of the link between half life constants. These principles are vital for learning or teaching and implementing knowledge in real-world circumstances.

Therefore if that you are a professional or researcher or student use the Half-Life Calculator right now to make your complicated decay calculations easier with a few clicks!

For more calculators follow:Calczon.com

One Reply to “Half-Life Calculator-half life formula”

Leave a Reply

Your email address will not be published. Required fields are marked *