What layer is primarily composed of iron and nickel and remains solid at Earth's center?

What layer is primarily composed of iron and nickel and remains solid at Earth's center?

• A. Outer Core
• B. Inner Core
• C. Mantle
• D. Crust

Answer: (B)

The center of Earth is dominated by an iron-nickel alloy whose state is controlled by extreme pressure. At Earth’s center, the crushing pressures are so immense that iron-nickel remains solid, forming the inner core. Surrounding this is a layer where the same alloy is liquid because, even though temperatures are very high, the pressure isn’t sufficient to keep it solid at those depths. This liquid outer core supports convection currents that help generate Earth’s magnetic field. The crust and mantle above are made mostly of silicate rocks, not iron-nickel. So the layer that is primarily iron-nickel and stays solid at the center is the inner core.

The center of Earth is dominated by an iron-nickel alloy whose state is controlled by extreme pressure. At Earth’s center, the crushing pressures are so immense that iron-nickel remains solid, forming the inner core. Surrounding this is a layer where the same alloy is liquid because, even though temperatures are very high, the pressure isn’t sufficient to keep it solid at those depths. This liquid outer core supports convection currents that help generate Earth’s magnetic field. The crust and mantle above are made mostly of silicate rocks, not iron-nickel. So the layer that is primarily iron-nickel and stays solid at the center is the inner core.