Who put forward the law of triads?
- Newlands
- Mendeleev
- Dobereiner
- Moseley
Show answer and solution
Correct answer: C. Dobereiner
1. Dobereiner observed elements grouped in threes (triads) with similar properties.
2. The atomic mass of the middle element was the mean of the other two.
3. Newlands proposed the law of octaves later.
4. So Dobereiner gave the law of triads.
_Source: syllabus Science Ch 5 'Periodic Classification of Elements'_