Question

In a first order of reaction the reacting substance has half-life period of ten minutes. What fraction of the substance will be left after an hour the raction has occurred ?
A. `1//6` of initial concentration
B. `1//64` of initial concentration
C. `1//12` of initial concentration
D. `1//32` of initial concentration

Answer 1

Correct Answer - B
`t_(1//2) = 10`
No. of half-life `= (60)/(10) = 6` half-life
`C_(t) = (C_(0))/(2)^(n) = (C_(0))/(2)^(6) = ((C_(0))/(64))`