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A certain first-order reaction is 58% complete in 95 s. What are the values of the rate constant and the half-life for this process?

User Fabianius
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1 Answer

3 votes

Answer:


0.005734 s^(-1) and 20.86 seconds are the values of the rate constant and the half-life for this process respectively..

Step-by-step explanation:

Expression for rate law for first order kinetics is given by:


a_o=a* e^(-kt)

where,

k = rate constant

t = age of sample


a_o = let initial amount of the reactant

a = amount left after decay process

We have :


a_o=x


a=58\%* x=0.58x

t = 95 s


0.58x=x* e^(-k* 95 s)


\k= 0.005734 s^(-1)

Half life is given by for first order kinetics::


t_(1/2)=(0.693)/(k)


=(0.693)/(0.005734 s^(-1))=120.86 s


0.005734 s^(-1) and 20.86 seconds are the values of the rate constant and the half-life for this process respectively..

User Joao Paulo
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