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प्रश्न
In a reaction between A and B, the initial rate of reaction (r0) was measured for different initial concentrations of A and B as given below:
| A/mol L−1 | 0.20 | 0.20 | 0.40 |
| B/mol L−1 | 0.30 | 0.10 | 0.05 |
| r0/mol L−1 s−1 | 5.07 × 10−5 | 5.07 × 10−5 | 1.43 × 10−4 |
What is the order of the reaction with respect to A and B?
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उत्तर
Suppose the order of the reaction with respect to A is m and with respect to B is n
∴ r0 = k[A]m [B]n
For the given data, we have
5.07 × 10−5 = k (0.20)m × (0.30)n ...(i)
5.07 × 10−5 = k (0.20)m × (0.10)n ...(ii)
1.43 × 10−4 = k (0.40)m × (0.05)n ...(iii)
Dividing eq. (i) by eq. (ii), we have
`(5.07 xx 10^-5)/(5.07 xx 10^-5) = (k (0.20)^m xx (0.30)^n)/(k (0.20)^m xx (0.10)^n)`
or 1 = (3)n
or n = 0
Dividing eq. (iii) by eq. (ii) and putting the value of n, we get
`(1.43 xx 10^-4)/(5.07 xx 10^-5) = (k (0.40)^m xx (0.05)^0)/(k (0.20)^m xx (0.10)^0)`
or, `(1.43 xx 10^-4)/(5.07 xx 10^-5)` = 2m
or (2)m = 2.82
or, m log10 2 = log10 2.82 = 0.45
or, m = `0.45/(log_10 2)`
= `0.45/0.3010`
= 1.49
= 1.50
Hence, order with respect to A = 1.5 and order with respect to 8 = 0.
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