Advertisements
Advertisements
प्रश्न
The time for half change in a first order decomposition of a substance A is 60 seconds. Calculate the rate constant. How much of A will be left after 180 seconds?
Advertisements
उत्तर
1. Order of a reaction = 1
`"t"_(1/2)` = 60 seconds,
k = ?
We know that, k = `0.6932/"t"_(1/2)`
k = `2.303/60` = 0.01155 s−1
2. [A0] = 100%
t = 180 s
k = 0.01155 seconds−1
[A] = ?
For the first order reaction k = `2.303/"t" log (["A"_0])/(["A"])`
0.01155 = `2.303/180 log (100/(["A"]))`
`(0.01155 xx 180)/2.303 = log (100/(["A"]))`
0.9207 = log 100 – log [A]
log [A] = log 100 – 0.9207
log [A] = 2 – 0.9207
log[A] = 1.0973
[A] = antilog of (1.0973)
[A] = 12.5%
APPEARS IN
संबंधित प्रश्न
Answer the following in one or two sentences.
How do the half-lives of the first order and zero-order reactions change with the initial concentration of reactants?
The rate of catalysed reaction is large than the uncatalysed reaction as _______.
Give one example of a pseudo first-order reaction.
Derive an integrated rate law expression for first order reaction: A → B + C
In a first order reaction \[\ce{x -> y}\]; if k is the rate constant and the initial concentration of the reactant x is 0.1 M, then, the half life is
Identify the order for the following reaction.
Radioactive disintegration of 92U238
A first order reaction has rate constant 1 × 10−2 s−1. What time will, it take for 20 g or reactant to reduce to 5 g?
The order of the reaction for which the unit of rate constant is s−1 is ____________.
For a zero order reaction, the plot of [A]t vs t is linear. The slope of the line is equal to ____________.
If the rate constant for a first-order reaction is k, the time (t) required for the completion of 99% of the reaction is given by:
