At the start of a reaction, concentration of reactants decreases:
Correct answer: C. Rapidly
- A. Slowly
- B. At constant rate
- C. Rapidly
- D. Exponentially
Explanation
At the start of a reaction, the concentration of reactants is highest, allowing for more frequent and effective collisions between molecules. This generally results in a rapid decrease in reactant concentration. Option C is correct because it captures this initial rapid decrease. Option A is incorrect because it inaccurately describes the typical initial behavior of many reactions. Option B fails to account for changes in reaction rate over time. Option D incorrectly suggests an exponential change, which is not typical for initial stages of reaction kinetics.
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About Chemical Equilibrium
Reversible reactions reach dynamic equilibrium when forward and reverse rates become equal, and Le Chatelier's principle predicts the effect of changing concentration, pressure or temperature. The chapter also covers solubility product, the common ion effect, buffer action and the conditions used in Haber's process, with equilibrium shifts distinguished from changes in the equilibrium constant.
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