Question

Outer most subshell wise electronic configuration of an element X is 3s2 3p4 and that of y is 3s1 a) find the valency x and y​

Answer 1

The electronic configuration in your question corresponds to phosphorus.

If you locate Phosphorus on the periodic table the element below it Arsenic.

The answer to your question is Atomic number 33, which is the atomic no. of Arsenic.

To check if this answer is correct, let's think through the rationale.

The numbers after the letter in your electronic configuration correspond to the number of electrons the element has, therefore:

2 + 2 +6 + 2 + 3 = 15

The atomic number of an element on the periodic table equal the number of electrons (and protons) the element has.

Locate atomic number 15 on the periodic table = Phosphorus

Below phosphorus is Arsenic on the periodic table.

Arsenic has the atomic no. 33 (means arsenic has 33 electrons and protons

Answer 2

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