The modern periodic law was given by whom?
- Henry Moseley
- Dmitri Mendeleev
- John Dalton
- Johann Dobereiner
Show answer and solution
Correct answer: A. Henry Moseley
1. Mendeleev arranged elements by atomic mass and gave the older periodic law.
2. Henry Moseley in 1913 showed that atomic number, not mass, decides periodicity.
3. The modern periodic law states that properties are periodic functions of atomic number.
4. So the law is credited to Moseley.
_Source: Selina Concise Chemistry ICSE Class 10, Ch 1 'Periodic Table' (aplustopper.com extract)_