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Question
Assertion: Separation of \[\ce{Zr}\] and \[\ce{Hf}\] is difficult.
Reason: Because \[\ce{Zr}\] and \[\ce{Hf}\] lie in the same group of the periodic table.
Options
Both assertion and reason are true, and reason is the correct explanation of the assertion.
Both assertion and reason are true but reason is not the correct explanation of assertion.
Assertion is not true but reason is true.
Both assertion and reason are false.
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Solution
Both assertion and reason are true but reason is not the correct explanation of assertion.
Explanation:
Although \[\ce{Zr}\] and \[\ce{Hf}\] lie in same group but As an effect of lanthanide contraction, zirconium and hafnium have similar radius of 160 pm and 159 pm respectively. Due to this similarity in their size, they show similar physical and chemical properties. As a result, \[\ce{Zr}\] and \[\ce{Hf}\] are difficult to separate. Both the statements assertion and reason are correct but reason is not the correct explanation of assertion.
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