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Half-Life and Radioactive Decay Calculator

Determine how much of a radioactive substance remains after any period of time, or back-calculate the half-life from measured decay data. Ideal for radiometric dating, nuclear physics coursework, and radiation safety assessments.

Initial Amount (N₀) (atoms)

Half-Life (years)

Time Elapsed (years)

Decay Type

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Chemistry

Thermodynamics and Enthalpy Calculator

Calculate Gibbs free energy and enthalpy changes for chemical reactions. Use this when predicting reaction spontaneity or thermodynamic feasibility at a given temperature and pressure.

Enthalpy Change (ΔH) (kJ/mol)

Entropy Change (ΔS) (J/(mol·K))

Temperature (K)

Pressure Correction

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Key differences

	Half-Life and Radioactive Decay Calculator	Thermodynamics and Enthalpy Calculator
Category	Chemistry	Chemistry
Inputs required	4	4
Result	Remaining Amount (atoms)	Gibbs Free Energy (ΔG) (kJ/mol)
What it does	Determine how much of a radioactive substance remains after any period of time, or back-calculate the half-life from measured decay data. Ideal for radiometric dating, nuclear physics coursework, and radiation safety assessments.	Calculate Gibbs free energy and enthalpy changes for chemical reactions. Use this when predicting reaction spontaneity or thermodynamic feasibility at a given temperature and pressure.