Question

An element x belong to third period and group 13 of modern periodic table .
Determine the valence electrons and valency of x.
Molecular formula of compound formed when x react with an element y whose atomic no is 8.
Write the name and the formula of the compound formed when x combine with chlorine

Answer 1

valence electrons of x is 3 and it's valency is 3.X is aluminum and element y is oxygen. when they react with each other it forms aluminum oxide(Al2O3). when X combine with chlorine it forms aluminum chloride (Alcl3).

Answer 2

Answer:

Given :

X belongs to period 3rd and group 13th.

Atomic number of X is 13.

Electronic configuration of X

= > 2 , 8 , 3

a ) .

Valance electron in 'X' is 3 .

Valency is 3 as it denote 3 electron to become stable.

b ) .

Given :

Atomic number of Y is 8

Electronic configuration of Y :

= > 2 , 6

Valency of Y is 2 as it need 2 electron to become stable.

Molecular formula X with Y is as :

X     Y

3    2

= > X₂Y₃

c ) .

Valency of X = 3

Valency of Cl = 1

Molecular formula of X with Cl :

X    Cl

3     1

= > XCl₃