Question

‘X’ is an element which belongs to VA group and 3rd period. The oxidation state and name of the element are​

Answer 1

Answer:

The element which belongs to 3rd period and group 2 is Magnesium.

Its electronic configuration is [Ne]3s

2

i) The no. of valence electrons =2

ii) Valency =2

iii) It is a metal as it belongs to the s-block.

Answer 2

Answer:

The element which belongs to the group VA, i.e., 15 and period 3rd is phosphorous.

The oxidation state of the element phosphorus varies from $+5$ to $-3$.

Explanation:

Given,

The element = X

Group = VA, i.e., group $15$

Period = $3rd$

The name of the element =?

As we know,

• From the modern periodic table, the element which belongs to the VA group and 3rd periods is phosphorous.

Phosphorus:

• The phosphorus symbol is P.

• The atomic number, Z, of phosphorus is $15$.

Therefore,

• The electronic configuration of P = $1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}$
• The outermost valence shell is $3s^{2}3p^{3}$.

Hence,

• The valence electrons in their outermost valence shell are $5$.

From this, we can say that,

• To get stability by attaining an inert gas configuration; Phosphorus can either lose $5$ electrons to attain a $+5$ oxidation state or gain$3$electrons to attain a $-3$ oxidation state.

Hence,

• The oxidation state of phosphorus varies from $+5$ to $-3$.