According to Oparin, which one of the following gases is absent in the primitive earth’s atmosphere?
CH4
O2
H2
Water vapor
As discussed in Chemical Evolution & Miller’s Experiment -
The Oparin-Haldane Theory:
According to Oparin, free oxygen was not present in the primitive earth’s atmosphere. However, Hydrogen, Nitrogen, Carbon dioxide or methane was present in large quantities. Hence, the correct option is (b).