A first order reaction is 20% complete in the 10 minutes. Calculate the time period for 75% completion of the reaction.

Explanation

`k = (2.303)/(t_1) "log " a/(a - x)`
`k = (2.303)/(t_10) "log" 100/80`
`k = 0.0223 "min"^(-1)`
`t_2 = (2.303)/(k) "log" a/(a - x)`
`t_2 = (2.303)/(0.0223) "log" 100/25`
`t_2 = 62.18 `min