Question

The decomposition of ammonia on tungsten surface at 500 K follows zero order kinetics . The half-life period of this reaction is 45 minutes when the initial pressure is 4 bar . The half life period (minutes) of the reaction when the initial pressure is 16 bar at the same temperature is
A. 120
B. 60
C. 240
D. 180

Answer 1

Correct Answer - d
For a zero order reaction
`t_(1//2) prop a_(0)` (initial concentration or initial pressure )
`(t_(1//2))_(1) prop P_(1)`
`(t_(1//2))_(2) prop P_(2)`
`((t_(1//2))_(2))/((t_(1//2))_(1)) = (P_(2))/(P_(1)) , (t_(1//2))_(2) = (16)/(4)`.
`(t_(1//2))_(2) = (16)/(4) xx 45` = 180 min