Hno3 | Preparation, Properties, Acidic Belongings |

Introduction:

HNO3, is a chemic of cracking commercial importance. There are 3 of import methods for its manufacture.

METHODS OF PREPARATION

Laboratory method:
From potassium nitrate (KNO3):
HNO3, tin hold upward prepared on large scale past times beating Republic of Chile tabular array salt petre amongst conc. H2SO4

COMMERCIAL METHOD:

General principle:

The nitrogen together with from the air tin hold upward made to combine past times electrical discharge. NO produced which is farther oxidized to NO2, together with is so dissolved inwards water.

Process:

N2 together with O2 from atmosphere are allowed to combine amongst each other is the presence of electrical are at 3000°C.

This reaction is endothermic together with is favoured at high temperature.The gases which come upward out from this electrical fieid incorporate 1. 25 % of NO. These gases are apace cooled downward to M °C.

At 600°C, NO combines amongst oxygen to shape NO2.

NO2 is cooled downward to 50°C past times H2O pipes. NO2 is absorbed inwards H2O inwards a tower inwards which the H2O trickles downward Fig (1.1)

HNO2 is oxidized to HNO3 together with NO. NO is re-oxidized to NO2 together with thence to HNO3.

Preparation of conc. HNO3:

• There are 3 stages to larn 100 % HNO3. Dil HNO3, obtained past times dissimilar methods tin hold upward concentrated to 68 % past times the procedure of distillation. This percent gives a constant boiling mixture. It is called commercial HNO3.
• If concentrated H2SO4, is used together with distilled amongst 68 % HNO3,, so nosotros larn 98% HNO3, H2SO4, absorbs the water.
• If nosotros desire to larn 100% HNO3, so 98% HNO3, is strongly cooled. Pure acid is deposited every bit colorless crystals at - 42°C. These crystals are separated together with melted to larn 100 % HNO3.

Physical properties:

1. Pure HNO3, is a colourless liquid
2. It has a feature choking smell
3. its B is 86°C
4. Its M.P. is - 42°C,
5. The specific gravity of pure HNO3, at 15°C is 1.538.
6. In the crystalline state, it is transparent
7. It is soluble inwards H2O inwards all proportions.
8. In moist air, it gives fumes.
9. It is hygroscopic inwards nature.

CHEMICAL PROPERTIES OF NITRIC ACID:

Decomposition:

HNO3, decomposes inwards the presence of lite fifty-fifty at ordinary temperature

Acidic property:

HNO3 is a potent acid. It ionizes inwards H2O to attain sufficient protons. it's dissociation constant is inwards the attain of 10^+3. On the solid seat down of acidic nature, it reacts amongst many oxides, hydroxides, carbonates bicarbonates, sulphites together with bisulphites. In this agency metallic nitrates are produced.

1. Reaction amongst calcium oxide (CaO):
   
2. Reaction amongst NaOH together with KOH:
   
   
3. Reaction amongst Na2 CO3:
   
4. Reaction amongst NaHCO3: