Solving Process

This is still about one of my favorite subject. I forgot the name of the chapter. But I really love this chapter :D

Washing Soda

-          Na₂CO₃ 10H₂O = Sodium carbonate deca hydrate

-          Na₂CO₃  = Soda ash

Preparation by Solvay Process :

NaCl + NH₃ + H₂O + CO₂ -> NH₄Cl + NaHCO₃

CaCO₃ -> CaO + CO₂

CaO + H₂O -> Ca(OH)₂

Ca(OH)₂ + 2NH₄Cl -> CaCl₂ + 2NH₃ + 2H₂O

2NaHCO₃ –-with catalyst---> Na₂CO₃ + H₂O + CO₂

Also known as :

CaCO₃  = Lime stone

CaO + CO₂ = Quick lime

Ca(OH)₂ = Slaked lime

Properties :

-          Efflorescence. Because Na₂CO₃ 10H₂O ---with sunlight--> Na₂CO₃  H₂O + 9H₂O

-          Alkaline in nature

-          Na₂CO₃ 10H₂O à Na₂CO₃ + 10H₂O

Uses :

-          Glass, soap, paper, and preparation of C compound like Borax and Caustic soda.

-          Removing permanent hardness in water.

-          Laundry (as washing soda).

-          Cleaning agent for domestic purposes.

-          As laboratory reagent.

Glass

-          Na₂O . CaO . 6SiO₂ = Batch

-          Batch + Glass pieces = Cullet

Preparation :

-          Na₂CO₃ + SiO₂ -> Na₂SiO₃ + CO₂

-          CaCO₃ + SiO₂ -> CaSiO₃ + CO₂

-          Annealing = Slow process and uniform cooling.

Uses and Properties can be read in here :)

Bleaching Powder

-          CaOCl₂ = Calcium oxychloride. It also known as Chloride of lime.

-          Ca(OH)₂ + Cl₂ --> CaOCl₂ + H₂O

Properties :

-          Yellowish-white color

-          It loses Cl₂ while doing action with acid (CO₂ / 2HCl / H₂SO₄)

Uses :

-          Bleaching cotton in textile industry

-          Bleaching wood pulp in paper factories

-          Washed clothes in laundry

-          Oxidizing agent

-          Disinfecting drinking water

Baking Soda

-          NaHCO₃ = Sodiumhydrogencarbonate

-          Preparation = Solvay Process

Properties :

-          Crystal, solid, transparent

-          White

-          Alkaline

-          Soluble in water

-          Aerate the dough. Because 2NaHCO₃ --heat--> Na₂CO₃ + H₂O + CO₂

Uses :

-          Neutralize excess acid (antacid)

-          Bakery as baking powder (NaHCO₃ and tartaric acid)

-          Fire extinguish (NaHCO₃ and sulphuric acid)

Plaster of Paris

-          CaSO₄ . ½ H₂O = Calcium Sulphate hemy hydrate

Preparation :

-          By heating Gypsum = CaSO₄ . 2H₂O

-          CaSO₄ . 2H₂O –with catalyst+374 K--> CaSO₄ . ½ H₂O + 1 ½ H₂O

Properties :

-          CaSO₄ . ½ H₂O + 1 ½ H₂O --> CaSO₄ . 2H₂O

Uses :

-          Making toys, decoration, jewellery, and cosmetics.

-          Medical applications.

-          Interior designs.

-          In laboratories -> For sealing the air gap.

Steel

-          Manufacture using Bessemer Converter :

2Mn + O₂ --> 2MnO

Si + O₂ --> SiO₂

2C + O₂ --> 2CO

MnO + SiO₂--> MnSiO₃ (slag)

4P + 5O₂--> 2P₂O₅

3CaO + P₂O₅ --> Ca₃(PO₄)₂ (slag)

Properties :

-          Quenching -- Cooling it by plunging into cold water (hard steel)

-          Tempering -- Cooled slowly (Elastic and much less brittle)

-          Annealing -- Adjusting the temperature and cooling slowly (soft steel)

Uses :

-          7 – 20% Mn - (hard & tough) steel helmets and rock crushing machinery, etc.

-          Cr & Ni - aeroplane parts, motorcars, bicycle parts, etc.

-          36% Ni - Scientific Instruments

-          46% Ni - Lamp bulbs and radio velves

-          35% Co - magnetism

-          35% Si - transformers and electromagnets

-          15% Si – pumps and pipes which carry acids.

-          15-20% tungsten + a lil vanadium + 5% Cr – drilling tools

-          18% Cr & Ni – Stainless steel, utensils, and surgical instrument  

Cement

Manufacture :

-          Raw materials : Lime stone and Clay

-          Composition :

CaO (60-70%)

SiO₂ (20-30%)

Al₂O₃ (5-10%)

Fe₂O₃ (2-3%)

-          In the ration 3:1 by mass

-          Heated to 1773 K in Rotary Kiln to produce clinker

-          It formed :

Ca₂SiO₄

Ca₃SiO₄

Ca₂Al₂O₆

-          And then mixed with (2-5%) Gypsum [CaSO₄ . 2H₂O]

Uses :

-          Cement + Sand --> Mortar

Used for plastering and binding bricks and stones.

-          Cement + Sand + Crushed stones --> concrete

Construction of buildings, roads, dams, bridges, etc.

-          Concrete + steel rods, bars, and other hard materials --> RCC (Reinforced Concrete Cement)

Used for making pipes, gutters, etc.

Lime

-          CaO = Quick lime

Manufacture by using Calcining

-          CaCO₃ -> CaO + CO₂  (a reversible reaction)

Properties :

-          Melting point = 2273 K

-          Produced brilliant white lime light when heated in an oxy-hydrogen flame.

-          When added to water, produced hissing sound + heat + slaked lime.
           [slaking of lime] CaO + H₂O -> Ca(OH)₂
           Reacts with moist HCl to form CaCl₂
           CaO + 2HCl -> CaCl₂ + H₂O
       
        Uses :
          Drying agent [ for drying ammonia and alcohol]
          Manufacture of CaCl₂, cement, and glass
          Making furnace lining as slaked lie
          White washing
 

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Different Types of Glass

This chemistry notes of mine was taken when I was preparing for my chemistry weekly test few years ago. I hope its useful :)

Soda Glass [Soft Glass]
- Cheapest and common.
- Prepared by fusing Soda Ash, Sand, and Limestone.
- Used for the manufacture of window glass, mirrors, common glassware, etc.
- Its easily attacked by chemicals.

Hard Glass
- Prepared by fusing Potassium Carbonate and Limestone.
- For making hard glass apparatus.
- Its more resistance to the action of Acids.

Lead Crystal Glass
- Potassium Carbonate, Sand, and Lead Oxide [PbO]
- Cut glasses show extraordinary sparkle.

Pyrex Glass [Borosilicate Glass]
- Mixture of Sand, Lime, Borax, and Alkali Carbonates.

- Borax (Na₂B₄O₇ 10H₂O)

- Good chemical durability and thermal shock resistance

- Used for making laboratory apparatus, ampoules, pharmaceutical containers, etc. and ovenware.

Optical Glass

- Used for aking lenses for spectacles, cameras, microscopes, telescopes, and other optical instruments.

Photochromatic Glass

- Temporarily darkens when exposed to sunlight because of the presence of silver bromide.

Safety Glass

- Prepared by placing a layer of transparent plastic between the 2 layers.

- Usually used to make wind screen of aeroplanes, automobiles, bullet proof glass, etc.

Glass fibre

- Excellent heat insulator.

- Optical fibre - used in telecommunications, surgical.

Coloured Glass

- By adding Metallic Oxides, Molten Mass, and certain colouring; such as :

Ferric Oxide : Brown

Chromic Oxide : Green

Manganese dioxide : Purple

Cobalt Oxide : Blue

- Used for manufacturing fancy articles, window panes, etc.

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