Chemical Kinetics

Integrated rate law equation for a first order gas phase reaction is given by (where Pi is initial pressure and Pt is total pressure at time t)

1. k = 2.303t Pi(2Pi - Pt)
2. k = 2.303t (2Pi - Pt)Pi
3. k = 2.303t Pi(2Pi - Pt)
4. k = 2.303t 2Pi(2Pi - Pt)

r = k[A] for a reaction, 50% of A is decomposed in 120 minutes. The time taken for 90% decomposition of A is minutes.

The rate of a first order reaction is 0.04 mol L-1 s-1 at 10 minutes and 0.03 mol L-1 s-1 at 20 minutes after initiation. Half life of the reaction is minutes. (Given 2 = 0.3010, 3 = 0.4771)

NO2 required for a reaction is produced by decomposition of N2O5 in CCl4 as by equation 2N2O5(g) 4NO2(g) + O2(g) The initial concentration of N2O5 is 3 mol L-1 and it is 2.75 mol L-1 after 30 minutes. The rate of formation of NO2 is x 10-3 mol L-1 min-1, value of x is . (nearest integer)

For a reaction taking place in three steps at same temperature, overall rate constant K = K1 K2K3. If Ea1, Ea2 and Ea3 are 40, 50 and 60 kJ/mol respectively, the overall Ea is kJ/mol.

The half-life of radioisotope bromine - 82 is 36 hours. The fraction which remains after one day is 10-2. (Given antilog 0.2006 = 1.587)

Consider the following data for the given reaction 2HI(g) H2(g) + I2(g) [figure] The order of the reaction is .

Time required for completion of 99.9% of a First order reaction is times of half life (t1/2) of the reaction.