Advertisements
Advertisements
प्रश्न
Solve
A first-order reaction takes 40 minutes for 30% decomposition. Calculate its half-life.
Advertisements
उत्तर
Given:
[A]0 = 100%, [A]t = 100 - 30 = 70%, t = 40 min
To find:
Half life of reaction (t1/2)
Formula:
`"k" = 2.303/"t" "log"_10 ["A"]_0/["A"]_"t"`
Calculation:
Substitution of these in above
`"k" = 2.303/"t" "log"_10 100/70`
= `2.303/"40 min" "log"_10 (1.429)`
= `2.303/"40 min" xx 0.155`
= 0.008924 min-1
t1/2 = `0.693/"k" = 0.693/(0.008924 "min"^-1) = 77.66 "min"`
The half life of reaction is 77.66 min.
APPEARS IN
संबंधित प्रश्न
Answer the following in brief.
What is a zeroth-order reaction?
Solve
The half-life of a first-order reaction is 1.7 hours. How long will it take for 20% of the reactant to react?
Answer the following in brief.
What are the units of the rate constant?
Derive the integrated rate law for the zeroth order reaction.
The rate constant of the first order reaction is 1.386 min–1. Calculate the time required for 80% reactant to decompose?
This reaction follows first-order kinetics. The rate constant at particular temperature is 2.303 × 10−2 hour−1. The initial concentration of cyclopropane is 0.25 M. What will be the concentration of cyclopropane after 1806 minutes? (log 2 = 0.3010)
Write the rate law for the following reaction.
A reaction that is `3/2` order in x and zero order in y.
Write the rate law for the following reaction.
A reaction that is second order in NO and first order in Br2.
What is the value of rate constant of first order reaction, if it takes 15 minutes for consumption of 20% of reactants?
The rate of the reaction \[\ce{A + B -> C}\] is 3.6 × 10−2 mol dm−3 s−1 when [A] = 0.3 mol dm−3 and [B] = 0.2 mol dm−3. Calculate k if reaction is first order in A and zero order in B.
For first order reaction the concentration of reactant decreases from 0.2 to 0.1 M in 100 minutes. What is the rate constant of the reaction?
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?
A first order reaction is 25% completed in 40 minutes. What is the rate constant k tor the reaction?
If time required to decrease concentration of reactant from 0.8 M to 0.2 M is 12 hours, the half life of this first order reaction is ____________.
Half-life period of a first order reaction, \[\ce{A -> product}\] is 3.0 hours. What is the value of rate constant?
In the reaction \[\ce{2SO2 + O2 -> 2SO3}\] the rate of appearance of SO3 is 4 × 10−4 M/s, the rate of disappearance of O2 is ____________.
The slope of a graph, log [A]t versus 't' for a first order reaction is −2.5 × 10−3 s−1. The rate constant for the reaction is ____________.
The time taken for 80% of a first order reaction to be complete is approximately ____________.
The rate of formation of B at time t for reaction \[\ce{2A -> 3B}\] is equal to ____________.
The time required to decompose SO2Cl2 to half of it's initial amount is 60 minutes. Calculate rate constant for this first order reaction.
A first order reaction, A → B takes 100 minutes for it's 90% completion. What is the rate constant of reaction?
For zero order reaction, when [A]t is plotted against time (t), the slope of the straight line obtained is equal to ______.
Define the half-life of a first-order reaction.
Which is the relation between half life and rate constant for a zero order?
A radioactive isotope decayed to 17/32 of its original mass after 60 minutes. Find the half-life of this radioisotope.
Which of the following correctly represents integrated rate law equation for a first order reaction in a gas phase?
A first order reaction takes 10 minute for 30% completion. Find rate constant of the reaction.
