1. Why are transition metals ions are coloured ?
2.Transitions metals are good catalyst. Why ?
3.Transition metals form alloy. Why ?
4. Why is a dip at Mn in the graph of melting point verses atomic number ?
5. What is lanthanoid contraction ?
ANSWER-
- due to d-d transition
- A. Due to having variable valences B. Due to having free valencies on surface.
- Due to having similar atomic sizes.
- Due to weak metallic bond beacuse of half filled electronic configuration.
- Decrease in the atomic size of Lanthanoids with atomic number
CHEMIGOD 