Q.

A(g)2B(g)+C(g) is a first order reaction. The initial pressure of the system was found to be 800 mm Hg which increased to 1600 mm Hg after 10 min. The total pressure of the system after 30 min will be ______ mm Hg. (Nearest integer)                 [2023]


Ans.

(2200)

A(g)2B(g)+C(g)t=0800--t=(10 min)800-P2PP

PT=800-P+2P+P

        =800+2P=1600

So P=400 mm

So t1/2=10 min

Given time = 30 min.

So for 1st order reaction Ct=C0(2)n

n=tt1/2=3010=3n=number of half life

Ct=800(2)3=100 mm of Hg

So After 30 minutes, P=700 mm

PA=800-700=100, PB=1400, PC=700

PT of reaction mixture =100+1400+700=2200 mm of Hg