Question 65 of 118

The t0.5 for the first order reaction.

PCl5(g) PCl3(g) + Cl2(g) is 20 min. The time in which the conc. of PClreduces to 25% of the initial conc. is close to 

1. 22 min

2. 40 min

3. 90 min

4. 50 min