# A first order reaction has rate constant k=5.5X10^-14s^-1 find its half life period. Also find time taken for 75% of reaction to over.

Dear Student

Rate Constant, k = 5.5 x 10-14 s-1

t1/2 = ???

We know,

t1/2 = $\frac{0.693}{k}$

= ​ = 0.126 x 1014 sec or 1.26 x 1013 sec

We know, for First Order Reaction-

Rate Constant, k =  ()
Now, t = ??? and x = 0.75 a

Therefore, t =  ()

= ​ (​$\frac{1}{0.25}$) = 0.418 x 1014 log (​$\frac{1}{0.25}$) = 4.18 x 1013 log 4

= ​4.18 x 1013 x 0.6020 = 2.516 x 1013 s

Regards

• 0
What are you looking for?