In the context of periodicity, which unit is used to measure the atomic radius of an element?
Correct Answer: Picometre
Subject: chemistry
- Nanometre
- Picometre
- Micrometre
- Millimetre
Explanation: • <b>Key Fact</b>
Atomic radius is measured in picometres (pm), where 1 pm = 10⁻¹² m.
• <b>Supporting Detail</b>
Typical atomic radii range from 30 pm to 300 pm.
• <b>Related Concept</b>
Angstrom (Å, 10⁻¹⁰ m) is also used in atomic measurements.
• <b>Why wrong options are wrong</b>
Nanometers (10⁻⁹ m), micrometers (10⁻⁶ m), and millimeters (10⁻³ m) are too large for individual atomic radii.
• <b>Exam Trick</b>
Pico = 10⁻¹² m (Atomic scale).
• <b>Additional Info</b>
Hydrogen has an atomic radius of approximately 37 pm.