Question

Which element pair correctly represents the dominant composition of the Earth's core?

• A. Silicon and Aluminum
• B. Iron and Magnesium
• C. Nickel and Iron
• D. Silicon and Magnesium

Answer 1

Answer:

C. Nickel and Iron

• Correct Answer: Option C (Nickel and Iron)

• The Earth's core is primarily composed of iron and nickel, making Option C the correct answer. The core consists of two distinct layers:

• Inner Core: This is a solid sphere composed mainly of iron (about 80%) and nickel (about 20%), along with small amounts of other elements. The extreme pressure at this depth (over 360 GPa) keeps it in a solid state despite temperatures reaching around 5,000-6,000°C.

• Outer Core: This is a liquid layer also dominated by iron and nickel in similar proportions. The lower pressure compared to the inner core allows this region to remain molten, and the movement of this liquid metal generates Earth's magnetic field through the geodynamo process.

• Why the other options are incorrect:

• Silicon and Aluminum : These are the dominant elements in Earth's crust, not the core

• Iron and Magnesium : While iron is correct, magnesium is more abundant in the mantle, not the core

• Silicon and Magnesium: These elements are primarily found in the mantle and crust