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Sir,will u please give extra more questions based on chapter "for stability"?

1. What specialty of the electronic configuration of ( Ne,Ar,Kr,Xe,Rn)  differs from that of helium ?

Except helium, all others have eight electrons in the outermost shell.

2. What is the reason for the stability of noble elements?

The reason for the stability of noble elements is the presence of eight electrons in the outermost shell.

3. What is the conclusion we reached about the relation between stability and electronic configuration?

Except helium, all other noble elements have eight electrons in their outermost shell and hence the atom is at the lower energy state. So the noble elements naturally have a stable structure. They combine with other elements only rarely.

4. What about helium? Draw its Bohr model of atom and examine. How can you describe stability of helium?

Helium, which has the smallest atom among inter elements, has only one shell. The maximum number of electrons that can be accommodated in the first shell is two. Hence, Two- electron arrangement is stable in the case of helium .

 The state in which eight electrons are present in the outermost orbitals is known as 'Octet arrangement '. Having 8 electrons in the outermost shell is the situation to attain the least energy level in an atom .

In order to attain stability ,atoms of an element without eight electrons in their outermost shell,changes to molecules of elements or compounds .

  The Bohr model of atom is shown below,

5. What is the charge of magnesium ion?

Magnesium ion gets 2 charge.It can be represented as ,

6. Both magnesium atom and oxygen atom are chargeless. What is the reason? Compare the Bohr model of both atoms with the table .

In the Bohr model of magnesium and oxygen atom,there is no charge due to the presence of equal number of positively charged protons and negatively charged electrons .

7. In what way did magnesium and oxygen attain stability.Write it on the basis of the changes taken place in the arrangement of electrons?

Magnesium (Mg) : Atomic number of magnesium is 12, so its electronic configuration is 2,8,2. Magnesium atom donates its two outermost electrons to an oxygen atom and forms magnesium ion.

Oxygen (O)           : Atomic number of oxygen is 8,so its electronic configuration is 2,6 .oxygen has 6 electrons in its outer most shell .Thus an oxygen atom accepts 2 electrons from magnesium atom and forms stable oxide ion .

8. How many electron did each chlorine atom share in the formation of a chlorine molecule ?

Each chlorine shares one electron each. Thus the eight electron (octet) arrangement is also formed by sharing electrons in this manner.

9. How many electrons did each oxygen atom share in the formation of oxygen molecule ?

Each oxygen atom shared one pair of electrons each.

10. How many electrons are either exchanged or shared by oxygen atom in magnesium oxide and oxygen molecule ?

In magnesium oxide, oxygen accepts two electrons and in oxygen molecule ,the number of electrons shared is four .

11. Frame a statement connecting outermost electrons (S) and valency.

The number of electrons released for accepted by the atom of an element during a chemical reaction is a measure of the valency of the atom. This is decided by the number of electrons in the outermost orbit of the atoms. So the electrons in the outermost orbit are called valence electrons.

12. What is the relationship between the number of electrons and the charge formed in each atom when magnesium oxide was formed?

Magnesium atom donates its two electrons and forms magnesium ion (Mg²⁺) with two units of positive charge.Oxygen atom accepts two electrons and forms oxide ion (O^2-) with two units of negative charge. When magnesium oxide is formed, the number of electrons released by magnesium and number of electrons accepted by oxygen are equal. Valency is the number which is equal to the charge of the ion.

13. Write the electronic configuration of each and complete the table.

14.Why don't inert gases take part in chemical bonding ?

Atoms takepart in chemical bonding to attain octet electron configuration in the outer most shell by decreasing the energy to the maximum extent .The inert gases have octet configuration in their outermost shell and hence they are already stable .So inert gases do not enter in chemical reactions .

15.Electrons in the outermost shell show greater tendency to takepart in chemical bonding .why ?

The attraction of nucleus on the electrons in the outer most shell will be less .Because of this  the high energy and less stable electrons are in the outer most shell .So they have greater tendency to take part in chemical bonding .