Which from following properties of lanthanoids is NOT true?
Which from following properties of lanthanoids is NOT true?
These are bad conductors of heat and electricity.
These are soft metals.
Coordination number is usually greater than six.
These are strongly paramagnetic.
Solution
(1) These are bad conductors of heat and electricity:
- This is incorrect. Lanthanoids are generally good conductors of heat and electricity, although they are not as good as transition metals.
(2) These are soft metals:
- This is true. Lanthanoids are relatively soft metals, especially the earlier ones in the series.
(3) Coordination number is usually greater than six:
- This is true. Lanthanoids, because of their large ionic radii, often have a coordination number greater than six, especially in complexes.
(4) These are strongly paramagnetic:
- This is true. Lanthanoids have unpaired f-electrons, making them paramagnetic. Some of them (especially those with a larger number of unpaired f-electrons) are strongly paramagnetic.