Valency of D is 5. A will be the most metallic element and have the largest atomic radii

Explanation:

Four element ABCD atomic numbers 12 13 14 and 15 respectively what is the number of valence electron and valency of D which of them will largest atomic radii which of these elements is most metallic

A with atomic number 12

B with atomatic number 13

C with atomatic number 14

D with atomatic number 15

Valency of an element is the capacity of an atom to combine with a particular number of atoms of another element.

A will have 2 valence electrons, B will have 3, C will have 4 and D will have 5 valence electrons.

Valency of D is 5.

A has the least atomic number among the given list and therefore it will have the largest atomic radii due to intermolecular attraction.

Also, element A has 2 electrons in the outer shell and it will tend to give away those electrons. So A will be the most metallic among the given list.

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