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Question
What are actinoids? Give three examples.
Solution
- The fourteen elements following actinium, i.e., from thorium (Th) to lawrencium (Lr) are called actinoids.
- All the actinoids are radioactive and most of them have short half-lives.
- The heavier members being extremely unstable and not of natural occurrence. They are produced synthetically by the artificial transformation of naturally occurring elements by nuclear reactions.
- Example: Thorium, Uranium, Plutonium, Californium.
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