Ionic Compounds

Question 1 What are ionic compound?

Question 2 What are covalent compounds?

Question 3 Define chemical bond?

Question 4 Why noble gases do not react?

Question 5 What are ions?

Question 6 How ions are formed?

Question 7 What are cations. How they are formed?

Question 8 Give example of cation formation?

Question 9 What are anions?

Question 10 How anions are formed. Give example?

How do Metals and Non-Metals react

When metals react with non-metals they form ionic compounds. When non-metals react with other non-metals, they form covalent compounds.

The force which links the atoms or ions in a molecule is called a chemical bond. The outermost electrons of an atom take part in a chemical reaction. Since the noble gases are chemically unreactive, we must conclude that the electron arrangement in their atoms are very stable which do not allow the outermost electrons to take part in chemical reactions.

The atoms combine with other atoms to achieve the inert gas electron arrangement and become more stable.

Ions

An ion is an electrically charged atom or group of atoms. An ion is formed by the loss or gain of electrons by an atom, so it contains an unequal number of electrons and protons.

There are two types of ions:

1) Cation

A positively charged ion is known as cation.

For Example : Na^+, Mg²⁺

A cation is formed by the loss of one or more electrons by an atom.

Na – e^– →  Na^{+
Z=11                  Z=10}
2,8,1                  2,8
K, L, M                  K, L

 

Mg – e^– → Mg^{2+
Z=12                 Z=10
2,8,2                  2,8
K, L, M                  K, L}

 

Al – e- → Al3+
 Z=13             Z=10
2,8,3             2,8
K, L, M             K, L

2) Anion

A negatively charged ion is known as anion.

For Example : Cl^{– ,} O^2-

An anion is formed by gain of one or more electron by an atom.

Cl + e^{– →} Cl^–
Z=17                 Z=18
2,8,7                  2,8,8
K, L, M                 K, L, M

 

O + e^–  → 0^2-
Z=8                 Z=10
2,6                    2,8
K, L                    K, L

 

N + e^– → N^3-
Z=7                  Z=10
2,5                      2,8
K, L                      K, L