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Question
Answer the following question:
Which element of the first transition series has highest third ionisation enthalpy?
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Solution
Among the elements of first transition series zinc has the highest third ionisation enthalpy. Electronic configuration of zinc is: \[\ce{3d^10 4s^2}\]
After the loss of two electrons from 4s orbital, Z and +2 Ion acquires \[\ce{3d^10}\] fully filled configuration which is highly stable therefore removal of third electron from \[\ce{3d^10}\] orbital will be more difficult and requires a large amount of energy.
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