Question

What is the relationship between two ions which have similar size and charge ?​

Answer 1

In each case, the negative ion is much larger than the atom from which it was formed. In fact, the negative ion can be more than twice as large as the neutral atom. The only difference between an atom and its ions is the number of electrons that surround the nucleus.

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Answer 2

Diagonal relationship arises when two ions which have similar size and charge due to the effect of charge and size.