Practice question · Select all that apply
Which statements about the first-order half-life are correct?
Hints
- Three follow from the same formula; one describes a different order entirely.
- The starting concentration cancels out of the first-order expression.
Show the answer
- A. Each successive half-life takes the same time
- C. It equals ln 2 divided by the rate constant
- D. It is independent of the starting concentration
Why
For first order, contains no concentration term, so it is constant throughout the reaction. Dependence on starting concentration is a feature of zero- and second-order kinetics.
Practise Reaction Kinetics
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