Advertisements
Advertisements
प्रश्न
Following data are obtained for reaction :
N2O5 → 2NO2 + 1/2O2
| t/s | 0 | 300 | 600 |
| [N2O5]/mol L–1 | 1.6 × 10-2 | 0.8 × 10–2 | 0.4 × 10–2 |
1) Show that it follows first order reaction.
2) Calculate the half-life.
(Given log 2 = 0.3010, log 4 = 0.6021)
उत्तर
1) For 1st order reaction the integral rate law is :
kt = `ln a_0/a_t`
Given
a0 = 1.6×10−2 mol L−1
For t = 300 s, at = 0.8×10−2 mol L−1
For t = 600 s, at = 0.4×10−2 mol L−1
Using first set of data in the rate law,
`k xx 300 = ln (1.6 xx 10^(-2))/(0.8xx 10^(-2))`
k = `0.00231 s^(-1)`
Using second set of data in the rate law,
`k xx 600 = ln (1.6 xx 10^(-2))/(0.4 xx 10^(-2))`
k = 0.00231 s-1
The value of k is consistent, therefore it follows first order reaction.
2) The half life of first order reaction is given by the following equation:
`t_(1/2) = (ln 2)/k = 2.303 xx (log 2)/k`
`:. t_(1/2) = 2.303 xx (log 2)/0.00231 = 300.08 s`
APPEARS IN
संबंधित प्रश्न
In a pseudo first order hydrolysis of ester in water, the following results were obtained:
| t/s | 0 | 30 | 60 | 90 |
| [A]/mol L−1 | 0.55 | 0.31 | 0.17 | 0.085 |
Calculate the average rate of reaction between the time interval 30 to 60 seconds.
For the decomposition of azoisopropane to hexane and nitrogen at 543 K, the following data are obtained.
| t (sec) | P(mm of Hg) |
| 0 | 35.0 |
| 360 | 54.0 |
| 720 | 63.0 |
Calculate the rate constant.
In the presence of acid, the initial concentration of cane sugar was reduced from 0.2 M to 0.1 Min 5 hours and to 0.05 Min 10 hours. The reaction must be of?
First order reaction is 50% complete in 1.26 × 1014s. How much time could it take for 100% completion?
In the first order reaction, half of the reaction is complete in 100 seconds. The time for 99% of the reaction to occurs will be
Observe the graph shown in figure and answer the following questions:
- What is the order of the reaction?
- What is the slope of the curve?
- Write the relationship between k and t1/2 (half life period).
For a first order reaction, the ratio of the time for 75% completion of a reaction to the time for 50% completion is ______. (Integer answer)
The slope in the plot of `log ["R"]_0/(["R"])` Vs. time for a first-order reaction is ______.
Radioactive decay follows first-order kinetics. The initial amount of two radioactive elements X and Y is 1 gm each. What will be the ratio of X and Y after two days if their half-lives are 12 hours and 16 hours respectively?
The rate constant for the reaction:
\[\ce{2N2O_{(s)} ->2N2O4_{(g)}}\] is 4.98 × 10-4 s-1.
The order of the reaction is ______.
