Oparin and Haldane proposed that "irst form of life could have come from pre-existing non-Living organic molecules (eg. RNA. protein etc.) and that formation of life was preceded by chemical evolution, le formation of diverse organic molecules from inorganic constituents The conditions on earth were high temperature. volcanic storms,reducing atmosphere containing `CH_4, NH_3`.etc. Reducing atmosphere promoted increased synthesis of energy rich molecules and abiotic synthesis of complex organic molecules took place
