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Questions
Compare the chemistry of actinoids with that of the lanthanoids with special reference to atomic and ionic sizes.
Compare the chemistry of actinoids with that of the lanthanoids in reference to atomic and ionic sizes.
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Solution
Both lanthanoids and actinoids show a decrease in the size of their atoms or ions in the +3 oxidation state. In lanthanoids this decrease is called lanthanoid contraction, while in actinoids it is called actinoid contraction. However, in actinoids, the contraction increases gradually due to the very low shielding effect of 5f-electrons from one element to another.
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