The correct option is 2 and 3 only.
Explanation
The evolution of the Earth's atmosphere is generally categorized into three stages: the loss of the primordial atmosphere, the hot interior contributing to the evolution of the atmosphere (degassing), and the modification of the atmospheric composition by the process of photosynthesis.
Statement-wise Analysis
- Statement 1 is Incorrect: The primordial atmosphere consisted chiefly of Hydrogen and Helium. These light gases were part of the solar nebula from which the planets formed. Nitrogen and Oxygen were not significant components of the primordial atmosphere; they accumulated later through degassing and biological processes.
- Statement 2 is Correct: The early atmosphere was stripped off by the impact of solar winds. In the early history of the solar system, the solar wind was intense enough to blow away the gaseous envelope of hydrogen and helium surrounding the protoplanets.
- Statement 3 is Correct: This phenomenon of atmospheric stripping occurred on Earth as well as on other terrestrial planets (Mercury, Venus, and Mars). Due to their proximity to the Sun and relatively lower gravity compared to Jovian planets, the terrestrial planets could not hold onto the light primordial gases against the force of the solar winds.
Key Takeaway: The Earth's primordial atmosphere (Hydrogen and Helium) was lost due to solar winds, distinguishing it from the secondary atmosphere formed later via volcanic degassing.