Question

According to oparin, which one of the following was not present in the primitive atmosphere of the earth

• A. Oxygen
• B. Hydrogen
• C. Water vapour
• D. Methane

Answer 1

The Correct Option is A

The question tests our understanding of the composition of the primitive atmosphere of the Earth according to the theory proposed by Alexander Oparin. Let's break down the options one by one to determine which was not present in the early Earth's atmosphere as per Oparin's theory:

1. Oxygen: According to Oparin, the primitive Earth's atmosphere was reducing, devoid of free oxygen. Oxygen appeared much later due to photosynthesis by early life forms.
2. Hydrogen: Hydrogen was indeed a component of the early atmosphere. It is a light and abundant element involved in forming basic compounds.
3. Water vapour: Water vapour was present and is believed to have played a crucial role in the formation of the early oceans and in chemical reactions on the primitive Earth.
4. Methane: Methane, a simple carbon compound, was also thought to be present in the early atmosphere. It contributed to the reducing conditions necessary for the formation of complex organic molecules.

Based on the above analysis, Oxygen is the only element that was not present in the primitive atmosphere according to Oparin's hypothesis.