11.2—The half-life of a reaction

Be able to calculate the half-life of a reaction, using data from a suitable graph, and identify a reaction with a constant half-life as being first order.

Use —the half-life of a reaction to connect the rule to the data and decision in the question.

This matters because —the half-life of a reaction determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the half-life of a reaction to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The half-life of a reaction is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.