Question

Which of the following statements in relation to the solar system is/are correct?

• A. The most abundant elements are H and He.
• B. The abundances of elements with atomic numbers 1-50 show an overall decreasing trend.
• C. The abundances of heavier elements (atomic number >50) are mostly higher than that of lighter elements (atomic number <50).
• D. Elements having odd atomic numbers are more abundant than their immediate neighbours.

Hint:

Hydrogen and helium dominate the solar system, and heavier elements are relatively less abundant.

Answer 1

The Correct Option is A, B

Step 1: Understanding the solar system's elemental composition.
Hydrogen (H) and Helium (He) are the most abundant elements in the universe, particularly in stars and the solar system. These two elements account for the majority of the universe's baryonic mass.

Step 2: Analyzing the options.
(A) The most abundant elements are H and He: Correct — Hydrogen and helium are the two most abundant elements in the solar system.
(B) The abundances of elements with atomic numbers 1-50 show an overall decreasing trend: Incorrect — While many elements show a decreasing trend, there are exceptions such as oxygen, carbon, and nitrogen.
(C) The abundances of heavier elements (atomic number >50) are mostly higher than that of lighter elements (atomic number <50): Incorrect — Lighter elements like H and He are more abundant than heavier elements.
(D) Elements having odd atomic numbers are more abundant than their immediate neighbours: Incorrect — This is not generally true, as abundance depends on various nuclear processes, not just atomic number parity.

Step 3: Conclusion.
The correct answer is (A) The most abundant elements are H and He.