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Pls help me i really need help

Pls help me i really need help-example-1
User Mbq
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1 Answer

6 votes

Answer:

13. t = 1183 min and 0.50 M.

14.
t_(1/2)=2.67x10^(-8)hr

Step-by-step explanation:

Hello!

13. In this case, according to the units, we infer this is a second-order reaction which has the following integrated rate law:


(1)/([A]) =(1)/([A]_0) +kt

Which can be solved for the time as shown below:


t=( (1)/([A])-(1)/([A]_0))/(k)

Thus, we plug in the given concentrations and rate constant to obtain:


t=( (1)/(0.250M)-(1)/(0.850M))/(0.002387M^(-1)min^(-1))\\\\t= 1183min

For the second part, we proceed by using the same rate constant and the new initial concentration as follows:


(1)/([A]) =(1)/([A]_0) +kt\\\\(1)/([A]) =(1)/(0.750M) +0.680M^(-1)min^(-1)*0.996min\\\\(1)/([A]) =1.99,M


[A]=0.50M

14. In this case, according to the units of the rate constant, we infer this is a zeroth-order reaction, therefore we compute the half-life has shown below:


t_(1/2)=([A]_0)/(2k)

Thus, we plug in to obtain:


t_(1/2)=(2.696x10^(-6)M)/(2*50.5M*hr^(-1))


t_(1/2)=2.67x10^(-8)hr

Best regards!

User Vineeth Pradhan
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