Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Physical: Chemical Kinetics

Question:

Decomposition of N2O5 is expressed by the equation N2O5 → 2NO2 + \(\frac{1}{2}\)O2. If rate of decomposition of N2O5 is 1.8 x 10-3 mol L-1 min-1, then what will be the rate of formation of O2 during the same time interval?

Options:

5.4 x 10-3 mol L-1 min-1 

3.6 x 10-3 mol L-1 min-1 

1.8 x 10-3 mol L-1 min-1 

0.9 x 10-3 mol L-1 min-1 

Correct Answer:

0.9 x 10-3 mol L-1 min-1 

Explanation:

Rate expression = -\(\frac{d[N_2O_5]}{dt}\) = \(\frac{1}{2}\)\(\frac{d[NO_2]}{dt}\) = 2\(\frac{d[O_2]}{dt}\)

\(\frac{d[O_2]}{dt}\) = -\(\frac{1}{2}\) x (-1.8 x 10-3) = 0.9 x 10-3 mol L-1 min-1