The correct option is 2 only
Explanation
The internal structure of the Earth evolved through specific geological processes that separated materials based on their physical properties and density during the planet's formative years.
- Statement 1 is Incorrect: The Earth's core was formed through the process of differentiation. In the early stages of Earth's history, the planet was mostly in a volatile, semi-molten state. Under the influence of gravity, heavier and denser materials sank towards the center, while lighter materials rose towards the surface. This separation led to the formation of distinct layers: the crust, mantle, and core.
- Statement 2 is Correct: The core is composed of heavy materials with high density, primarily Nickel and Iron (collectively referred to as NIFE). Lighter materials, such as silica, are predominant in the crust (SIAL - Silica and Aluminium) and the mantle (SIMA - Silica and Magnesium).
- Statement 3 is Incorrect: Degassing is the process responsible for the formation of the Earth's atmosphere and hydrosphere. It involves the release of gases and water vapor from the Earth's interior through volcanic eruptions and fissures. It is not the mechanism behind the formation of the core.
Key Takeaway: The Earth's interior layers formed via differentiation (density separation), while the atmosphere formed via degassing.