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d-and f-Block Elements — Chemistry STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceChemistryd-and f-Block Elements5 Marks
Question
What is the difference between lanthanoids and actinoids?
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Answer

Difference between Lanthanoids and Actinoids:
LanthanoidsActinoids
1. Besides +3 oxidation state, they show +2 and +4 oxidation states only in few cases.1. Besides +3 oxidation state, they show higher oxidation states of +4 , $+5,+6$ and +7 also.
2. Most of their ions are colourless.2. Most of their ions are coloured.
3. They have less tendency towards complex forma-tion.3. They have greater ten-dency towards complex formation.
4. Lanthanoid compounds are less basic.4. Actinoid compounds are more basic.
5. Do not form oxocations.5. From oxocations e.g. $UO _2^{2+}, PuO _2^{2+}$ and $UO ^{+}$.
6. Except promethium, they are non-radioactive.6. They are radioactive.
7. Their magnetic properties can be explained easily.7. Their magnetic properties cannot be explained easily.

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