According to modern science, what was the approximate chemical composition of the solar nebula?

• A. About 50% hydrogen, 30% helium, and 20% heavier elements by mass
• B. About 60% hydrogen, 35% oxygen, and 5% heavier elements by mass
• C. About 74% hydrogen, 24% helium, and 2% heavier elements by mass
• D. About 90% helium, 5% hydrogen, and 5% heavier elements by mass

Answer: (C)

Verified step by step guidance

1. Understand that the solar nebula refers to the cloud of gas and dust from which our solar system formed.
2. Recall that the chemical composition of the solar nebula is primarily based on observations of the Sun and primitive meteorites, which reflect the original material of the solar system.
3. Recognize that hydrogen and helium are the most abundant elements in the universe, especially in primordial clouds like the solar nebula.
4. Note that heavier elements (often called 'metals' in astronomy) make up only a small fraction of the total mass compared to hydrogen and helium.
5. Summarize that the approximate mass composition of the solar nebula is about 74% hydrogen, 24% helium, and 2% heavier elements, reflecting the primordial cosmic abundances.