Question

atomic number of an element is 17 . what is its valency and valence electrons??

Answer 1

its valency is 1. and valence electron ic 7.

Answer 2

Hey There! ☺

Answer :

Atomic No. = No. of Electrons = No. of Protons

So, we can conclude that the element has 17 electrons in total.

Now, Electronic Configuration of the element :

K         L          M
2          8          7

That is, the element is configured as (2,8,7).

♦ Thus, valence electrons (electrons in outermost shell) = 7

The element can be stable by being octant, i.e, having 8 electrons in valence shell.

For that, it must gain 1 more electron.

Therefore,

♦ Valency = 1

Additional Info : The element with atomic number 17 is Chlorine (Cl). Find the electronic configuration of this element attached here.

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Hope my answer helped... ☺☺☺