Question

For a first order reaction it takes 5 mins for an initial concentration of 0.6 mol per Litre to become 0.4 mole per litre. How long will it take for the initial concentration to become 0.3 mol per litre.

Answer 1

\[k=\frac{ 2.303 }{ t }\log _{10}\frac{ A _{0} }{A }\] is the formula to use where A0 is the initial conc and A is the final conc.

Answer 2

yaa first find the K using all the variables
and then find t putting A, A0 and K value in the equation
its like reverse :)got it

Answer 3

or u can apply half life to right here the product decreased from 0.6 mole to 0.3 mole is it not half :) i forgot what is half life mean in kinetics

Answer 4

this is not the half life concept.....i got the answer 6.67 min.......please tell me if thats correct

Answer 5

how did you do that

Answer 6

i know it should be more than 5 :)

Answer 7

using the formula.....first i found the value of k which came out to be 0.691 1/min then i substituted the value of k for the equation where i had to find the time taken and so i got the time as 6.67 min. In the first substitution i used 0.4 as the final conc. and in the second i used 0.3....i jus want to know if my answer is correct. There is no ans given in the textbook

Answer 8

yaa Ur right if u have calculations are correct :)

Answer 9

hmmmm.....alright...will stick to that thanks

Answer 10

ur welcome :)

Answer 11

hey there is one calculation mistake.....the time taken is 8.56 mins.....this happened because of the log function..

Answer 12

ok may be i have not caluclated i just given u how to do :)anyway good

Answer 13

This may help: http://is.gd/iJsWqE