For a chemical reaction:
A + B → Products
| Experiment | [A] mol L-1 | [B] mol L-1 | Initial rate mol L-1 s-1 |
| 1. | 0.1 | 0.1 | 2.0 x 10-3 |
| 2 | 0.2 | 0.2 | 4.0 x 10-3 |
| 3. | 0.1 | 0.2 | 2.0 x 10-3 |
What is the overall order of the reaction?
Answer & explanation
Correct answer: option 2
For a chemical reaction:
A + B → Products
Rate = k [A]x [B]y
2.0 x 10-3 = k [0.1]x [0.1]y ....(i)
4.0 x 10-3 = k [0.2]x [0.2]y ....(ii)
2.0 x 10-3 = k [0.1]x [0.2]y .....(iii)
Dividing (ii) by (iii), we get
\(\frac{4.0 × 10^{-3}}{2.0 × 10^{-3}}\) = 2x
21 = 2x
x = 1
Dividing (iii) by (i), we get
\(\frac{2.0 × 10^{-3}}{2.0 × 10^{-3}}\) = 2y
20 = 2y
y = 0
Rate = k [A]1 [B]0
Overall order = 1 + 0 = 1