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Half-Life definitions

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  • Half-life
    Time required for half of a substance to decay or decompose, varying with reaction order.
  • Zero-order reaction
    Reaction where half-life is directly proportional to initial concentration and inversely to rate constant.
  • First-order reaction
    Reaction where half-life is constant and independent of initial concentration, common in radioactive decay.
  • Second-order reaction
    Reaction where half-life increases as initial concentration decreases, dependent on rate constant and concentration.
  • Rate constant
    Proportionality constant in the rate equation, denoted as k, affecting half-life calculations.
  • Initial concentration
    Starting amount of reactant, influencing half-life in zero and second-order reactions.
  • Radioactive decay
    Process following first-order kinetics where unstable nuclei lose energy by emitting radiation.
  • Molarity
    Concentration unit of a solution, expressed as moles of solute per liter of solution.
  • Time inverse
    Unit indicating the reciprocal of time, used in rate constant units for first-order reactions.
  • ln(2)
    Natural logarithm of 2, approximately 0.693, used in first-order half-life calculations.