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Question
What are chemical twins? Write ‘two’ examples.
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Solution
Chemical twins are those in which the properties of some elements are same. Atomic size of Zr and Hf , Nb and Ta are similar. This is due to Lanthanide contraction.
Example - Zr and Hf ; Nb and Ta
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| Column I (Compound/element) | Column II (Use) | |
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