Question

Elements in the same group show similarities
and gradation in their properties.​

Answer 1

Answer:

a) Elements in the same group have similar properties because they have the samenumber of valence electrons in their outermost shell. ... Therefore, both these elements belong to the same group. Atomic number of elementX = 17. Electronic configuration of element X is 2, 8, 7.

Answer 2

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Elements in the same group have similar properties because they have the same number of valence electrons in their outermost shell. ... Element with atomic number 12 will have similar physical and chemical properties as element with atomic numbers 20 and 38. Because the number of electrons in outermost shell are same.