Question

an element x belong to 3rd period and a group 13 of a moderm periodic table determine the valence electron and valency of x and also find molecular formula of the compound formed when x reacts with a element y ( atomic no 8 )

Answer 1

Given:

Location of element X in periodic table = Third period and 13th group.

To find:

Valance electron in element X = ?

Valency of element X = ?

molecular formula of the compound formed when x reacts with a element y = ?

Solution:

• As per the given condition, the element which is located in the 13th group and the third period is Aluminium. Thus element X is identified as Aluminium.
• The electron which is present in the outermost shell it is called a valence electron. The electronic configuration of aluminium is 2, 8, 3.
• As the outermost shell has three electron, aluminium has 3 valence electrons.
• The valance electron of aluminium is 3. It means that it loses 3 electron to attain octet and thus its valency is +3.
• The element with atomic number 8 is oxygen. When aluminium (X) reacts with oxygen (Y) it leads to the formation of Aluminium oxide with molecular formula $Al_2O_3$.
• The chemical equation involved in the reaction is as follows

$4Al+ 3O_2\rightarrow 2Al_2O_3$

Learn more about such concept

An element ‘a' belongs to 3rd period and 17th group of the periodic table.

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An atom of an element has three electron in its M shell:a)writes its electronic configuration and atomic number.b)what is its valency.c)identify the element and also write its nature.

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Read more on Brainly.in - https://brainly.in/question/1747984#readmore

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