He following three-step mechanism has been proposed for the decomposition reaction, 2NO2Cl(g)→2NO2(g)+Cl2(g)

:

Step 1 2NO2Cl(g)⇌ClO2(g)+N2O(g)+ClO(g)
Step 2 N2O(g)+ClO2(g)⇌NO2(g)+NOCl(g)
Step 3 NOCl(g)+ClO(g)→NO2(g)+Cl2(g)

it's all four options.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8

the answer is 0.42 is that is an option. this question provides no info