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Q1
(CISF/2025)
Science & Technology › Basic Science (Physics, Chemistry, Biology)
Which one of the following elements is higher in concentration in a human body ?
Result
Your answer:
—
·
Correct:
D
Explanation
The human body is composed of various chemical elements, and their concentration is typically measured by mass percentage. The four most abundant elements in the human body are Oxygen, Carbon, Hydrogen, and Nitrogen.
- Oxygen (O): Approximately 65% of body mass. It is a major component of water (H2O) and organic compounds.
- Carbon (C): Approximately 18.5% of body mass. It forms the backbone of all organic molecules.
- Hydrogen (H): Approximately 9.5% of body mass.
- Nitrogen (N): Approximately 3.2% of body mass, found in proteins and nucleic acids.
While hydrogen atoms are the most numerous by count (atomic percentage), Oxygen is the highest in terms of mass concentration because each oxygen atom is significantly heavier than a hydrogen atom.
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SIMILAR QUESTIONS
Which one of the following gases, present in the air near the surface of the Earth, has maximum concentration?
Which one among the following elements has the highest catenation property?