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Question
Why does the rate of any reaction generally decreases during the course of the reaction?
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Solution
The rate of a reaction depends on the concentration of reactants. As the reaction progresses, the concentration of reactants decreases because the reactants start getting converted to products. Hence the rate decreases.
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| [NO] | [H2] | Rate | |
| Mol L-1 | Mol L-1 | Mol L-1 s-1 | |
| (1) | 8 × 10-5 | 8 × 10-5 | 7 × 10-9 |
| (2) | 24 × 10-5 | 8 × 10-5 | 2.1 × 10-8 |
| (3) | 24 × 10-5 | 32 × 10-5 | 8.4 × 10-8 |
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