Interpret concentration-time graphs.

In the subtopic Rate equations and orders (A-level only), this AQA A-Level Chemistry 7405 learning objective focuses on interpret concentration-time graphs. It belongs to Rate equations (A-level only), so revision should stay anchored to this exact subtopic rather than drifting into a generic GCSE-level chemistry summary. Approved keywords to use include concentration-time. Concentration-time graph. means a graph that plots the concentration of a reactant or product against time, showing how concentration changes during a reaction Avoid the mistake of students often misinterpret the slope of a concentration-time graph, thinking it indicates the rate of reaction directly; instead, the slope of a concentration-time graph represents the change in concentration over time, not the rate itself. To find the rate, calculate the gradient at a specific point on the graph For exam answers, when interpreting concentration-time graphs, identify the shape of the curve to determine the reaction order. A straight line indicates zero-order, a curve that flattens indicates first-order, and a curve that steepens indicates second-order