Question

elements of second period show resemblance in properties with the 3rf period element diagonally ?​

Answer 1

Answer:

helium

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Answer 2

Answer:

On moving across a period, the size of atoms decreases and on moving down a group the size of atoms increases. The effects seem to cancel out. Similar to size, covalence, basic nature, electronegativity also cancel out differences. So these diagonally next elements in 2nd and 3rd periods have similar chemistry

Explanation:

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