Saved Bookmarks
| 1. |
Explain the formation of coloured ions by lanthanoids |
|
Answer» Solution :Many TRIVALENT ions `(M^(3+))` in lanthanoids show colour in both SOLID as well as in aqueous state. The formation of colour can be explained by `f- f` transition. However, absorption bands are narrow. The tripositive lanthanoid ion having `4f^(n)` configuration has same colour as tripositive lanthanoid ion having `4f^(14-n)` configuration. Ex: `ND^(3+) (4f^(3)) and Er^(3+ )4f^(11))` both show red colour. `LA^(3+), GD^(3+) and Lu^(3+)` are colourless because of `f^(0), f^(7) and f^(14)` configurations respectively. |
|