Concept:In a concentration-time graph, the instantaneous rate of the reaction is equal to the mathematical slope of the tangent to the curve at any given point.
Formula:$$ \text{Rate} = |\text{Slope}| = \left| \frac{dC}{dt} \right| $$
Solution:- The steeper (greater) the slope of the curve, the faster the concentration is changing per unit of time.
- Near the start of a reaction, reactant concentrations are at their highest, leading to the maximum number of collisions.
- Therefore, a greater slope directly translates to a greater (faster) rate of reaction.
Why other options are incorrect:A lesser slope means a slower reaction. Constant slope implies a zero-order reaction. Equilibrium occurs when the slope becomes exactly zero (flat horizontal line).
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