Answer:
(12) For first-order reaction rate law is
ln[A]=-kt + ln[A]0
where [A]0=initial concentration of A,
k=rate constant, [A]= concentration of A at time t.
Given [A]0=8.30 M, k=0.428 s-1, [A]=? at time t=15 s.
ln[A]=(- 0.428 s-1 x 15 s) + ln[8.30]
ln[A]=-4.3
[A]=e-4.3=0.0135 M.
[A]=0.0135 M.
(13) For first-order reaction rate law is
1/[A]=kt + 1/[A]0
where [A]0=initial concentration of A,
k=rate constant, [A]= concentration of A at time t.
Given [A]0=8.3 M, k=0.428 M-1 s-1, [A]=5 M at t=?
1/(5M)=(0.428 M-1 s-1 x t) + 1/(8.3 M)
(0.428 M-1 s-1 x t)=0.0795 M-1
t=(0.0795 M-1)/(0.428 M-1 s-1)
t=0.1858 s.
(14) Given rate constant, k=9.012 x 10-3 M s-1 and [O3]0=0.322 M
From the units of rate constant, the order od reaction is zero order.
Therefore half-life for the zero-order reaction is
t1/2=[A]0/2k
where [A]0=initial concentration and t1/2=half life.
Therefore here t1/2=[O3]0/2k=(0.322 M)/(2 x 9.012 x 10-3 M s-1)
t1/2=17.865 s.
Please let me know if you have any doubt. Thanks
Question 12 What is the concentration of reactant [A] at t = 15.00 s if A...
A reactant decomposes with a half-life of 167 s when its initial concentration is 0.301 M. When the initial concentration is 0.661 M, this same reactant decomposes with the same half-life of 167 s. What is the value and unit of the rate constant for this reaction? What is the order of the reaction? K=? also k =0.00475 s-1 is not the answer
The integrated rate law allows chemists to predict the reactant concentration after a certain amount of time, or the time it would take for a certain concentration to be reached. The integrated rate law for a first-order reaction is: [A]=[A]0e−kt Now say we are particularly interested in the time it would take for the concentration to become one-half of its initial value. Then we could substitute [A]02 for [A] and rearrange the equation to: t1/2=0.693k This equation calculates the time...
A reactant decomposes with a half-life of 157 s when its initial concentration is 0.240 M. When the initial concentration is 0.782 M, this same reactant decomposes with the same half-life of 157 s.If the reaction order is 1 what is the k value ?
A particular reactant decomposes with a half-life of 131 s when its initial concentration is 0.285 M. The same reactant decomposes with a half-life of 221 s when its initial concentration is 0.169 M. Determine the reaction order. What is the value and units of the rate constant for this reaction? Units k =
A particular reactant decomposes with a half-life of 139 s when its initial concentration is 0.356 M. The same reactant decomposes with a half-life of 233 s when its initial concentration is 0.212 M. Determine the reaction order. 0 2 1 What is the value and unit of the rate constant for this reaction? k=? units=?
The half-life of a reaction, t1/2, is the time it takes for the reactant concentration [A] to decrease by half. For example, after one half-life the concentration falls from the initial concentration [A]0 to [A]0/2, after a second half-life to [A]0/4, after a third half-life to [A]0/8, and so on. on. For a first-order reaction, the half-life is constant. It depends only on the rate constant k and not on the reactant concentration. It is expressed as t1/2=0.693k For a...
The integrated rate law allow chemists to predict the reactant concentration after a certain amount of time, or the time it would take for a certain concentration to be reached. The integrated rate law for a first-order reaction is: [A] = [A]oe -Rt Now say we are particularly interested in the time it would take for the concentration to become one-half of its initial value. Then we could substitute Z" for [A] and rearrange the equation to: A) 1/2= 0093...
A reactant decomposes with a half-life of 11.5 s when its initial concentration is 0.150 M. When the initial concentration is 0.875 M, this same reactant decomposes with a half-life of 67.1 s. What is the order of this reaction? What is the value and unit of the rate constant for this reaction?
A reactant decomposes with a half-life of 48.3 s when its initial concentration is 0.118 M. When the initial concentration is 0.240 M, this same reactant decomposes with a half-life of 98.3 s. What is the order of the reaction? 01 O2 00 What is the value and unit of the rate constant for this reaction? Unit: M-s-1
A reactant decomposes with a half-life of 35.1 s when its initial concentration is 0.359 M. When the initial concentration is 0.733 M, this same reactant decomposes with a half‑life of 71.7 s. What is the order of the reaction? 1 2 0 What is the value and unit of the rate constant for this reaction? ?= Unit: