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)
Advertisements
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
The time required for 10% completion of a first order reaction at 298 K is equal to that required for its 25% completion at 308 K. If the value of A is 4 × 1010 s−1. Calculate k at 318 K and Ea.
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
A definite volume of H2O2 undergoing spontaneous decomposition required 22.8 c.c. of standard permanganate solution for titration. After 10 and 20 minutes respectively the volumes of permanganate required were 13.8 and 8.25 c.c. The time required for the decomposition to be half completed is ______ min.
The reaction \[\ce{SO2Cl2(g) -> SO2(g) + Cl2(g)}\] is a first-order gas reaction with k = 2.2 × 10−5 sec−1 at 320°C. The percentage of SO2Cl2 is decomposed on heating this gas for 90 min, is ______%.
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 ln[R] vs. time for a first order reaction is ______.
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 following data were obtained during the decomposition of SO2Cl2 at the constant volume. SO2Cl2 →SO2(g) + Cl2(g)
| Time (s) | Total Pressure (bar) |
| 0 | 0.5 |
| 100 | 0.6 |
Calculate the rate constant of the reaction.
Write the equation for integrated rate law for a first order reaction.
