For the first order reaction, calculate the ratio of the time taken to complete `99%` of the reaction to the time taken to complete `90%` of the reaction.
The half-life period for first order reaction is given by:
`t_(1//2) = 0.693/k` or `k=0.693/t_(1//2)`
Therefore, `k_(1) = 0.693/(30 min) = 0.231 min^(-1)` and `k_(2) = 0.693/(10 min) = 0.0693...
Correct Answer - A
a) `k=0.693/100 s^(-1)`
`t(99.9%) = 2.303/k log a/(a-x)`
`=(2.303 xx 100s/(0.693)) xx log 100/1`
`=(2.303 xx 100 xx 2)/(0.693) = 666.64` s
Correct Answer - D
The fraction of A and B remaining at time t when 99% of A has reacted, are (A=0.01, B=0.99)
`k_A=1/t` In 100 and `k_B=1/t` In `100/99`
`:....
Correct Answer - A
For zero order reaction,
x=kt
`:. (a)/(2)=kxxt_(1//2),i.e.,t_(1//2)=(a)/(2k)" ".....(i)`
For frist order reaction,
`t_(1//2)=(log_(e)2)/(k)" ".....(ii)`
From eqs. (i) and (ii), `(a)/(2k)=(log_(e)2)/(k)`
`a=log_(e)4M`