Explain the lowry bronsted theory of acids and bases

1. Explain the Lowry- Bronsted theory of acids and bases with a suitable
example.
2. Explain the Lewis concept of acids and bases with examples.Mention
its advantages also.
3. Define pH. Calculate the pH of a solution whose Hydrogen ion
concentration is 1x10 gramions / litre.
4. Write a note on indicators.
5. Write a note on applications of pH in industries.
6. Explain oxidation and reduction by electronic concept.
1. The hydrogen ion concentration of a solution is 2x10 gramions/litre
Calculate the pH of the solution.
2. The hydroxyl ion concentration of a solution is 1x10 gram ion/litre.
Calculate the pH of the solution.
3. The pH of a solution is 4.28.Calculate the hydrogen ion concentration
of the solution.
-6
-4
-9
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4. The pH of a solution is 11.5. Calculate the hydrogen ion concentration
of the solution.
Try to apply the Lewis theory and explain the following compounds
as acid or base.
Al Cl ZnCl
TEST YOUR UNDERSTANDING
3, 2
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1.4. CHEMICAL BONDING
1.4.1 Introduction
Definition
1.4.2 Types of Bonding
(1) Ionic bond
Example : Formation of Sodium Chloride
Explanation:
When two atoms in a molecule strongly tend to remain together, they
are said to be in chemical bonding with each other. In other words, it is
said that a chemical bond has been established between the two atoms.
“Achemical bond may be defined as an attractive force which holds
together the constituent atoms in a molecule”
According to Kossel and G.N.Lewis (1916) who put forward the
octet theory of valency, assumed that all atoms have a tendency to
acquire a stable grouping of 2 or 8 valence electrons as the elements in
the zero group (Noble gases). Thus it may be concluded that it is the
tendency of the atoms to acquire a stable configuration or to complete
their outermost orbit which is the cause of the chemical combination
between them.
(I) Ionic bond (or) Electrovalent bond or Polar bond
(ii) Covalent bond or Non-Polar bond
(iii) Co-ordinate covalent bond or Dative bond
(iv) Metallic bond.
This type of bond is formed as a result of the complete transfer of
one or more electrons from one atom to other.
This bond is generally present in inorganic compounds
The atomic number of sodium is 11.
The electronic configuration is 1s , 2s , 2p , 3s (2,8,1).
The electron dot formula is Na
Sodium has only one electron in its outermost orbital.
2 2 6 1
. ·
Cl
. .
.
. .
. .
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The atomic number of chlorine is 17.
The electronic configuration is 1s , 2s , 2p , 3s , 3p (2,8,7)
The electron dot formula is
Sodium has one electron in excess of the stable Neon configuration
(2,8). While chlorine is one electron short of the stable Argon
configuration (2,8,8).
By transferring one electron to chlorine, sodium acquires a unit
positive charge. The chlorine atom after gaining one electron acquires a
unit negative charge.
These charged ions are held together by electrostatic force of
attraction and form a neutral molecule of sodium chloride.