Question

Two elements are represented as
35. 24
X and Y
17. 12
(A) which of the element lose and gain electrons
(B) write the electronic
configuration of X and Y
(C) write the valency of X and Y

Answer 1

(A)- electronic configuration of element x=2,8,7
it needs one electron to complete its octet so
element x will gain electron.
hence its valency will be -1

electronic configuration of element y= 2,8,2
it is easier for this element to donate electrons than to gain electrons.
hence element y will donate electrons.
therefore ita valency will be +2.

hope it helps you

Answer 2

Question :

Two elements are represented as

35. 24

X and Y

17. 12

(A) which of the element lose and gain electrons

(B) write the electronic

configuration of X and Y

(C) write the valency of X and Y

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Answer :

Configuration of X = 17

                               = 2 , 8 , 7

Configuration of Y = 12

                               = 2 , 8 , 2

Element X will gain 1 electron in order to complete its octet .

Element Y will lose 2 electrons to complete octet .

Valency of X and Y

X = 2 , 8 , 7

Now X will gain 1 electron to complete octet .

Hence valency = - 1 as it will acquire negative charge !

Y = 2 , 8 , 2

Y will lose 2 electrons to complete octet.

Hence valency of Y = +2 as it acquires positive charge on losing electrons !

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