Material used in daily life

Cement: It is complex mixture of calcium silicate and Calcium aluminate.

Raw materials to prepare cement

Calcium Carbonate (CaCO₃), Special type of clay (Al₂O₃ SiO₂), Gypsum(CaSO₄ H₂0)

Chemical reaction

2CaCO₃+Al₂O₃ SiO₂ →→CaSiO₃+CaAl₂O₃+2CO₂ (Heat 1400°C-1600°C)

Manufacture process:

1) Crushing and Grinding

2) Slurry formation

3) Heating of slurry: When slurry mixture of calcium carbonate and special type of clay is heated into rotary kiln at temperature of 1400°C to 1600°C Red balls of cement are formed which is known as cement clinker.

4) Management of gypsum: Cement clinkers are mixed with Gypsum(CaSO₄ H₂0) which help to improve quality of cement as well as increase its setting time.

5) Final grinding: The mixture is finally grinded into powder, which is called cement. It is packed into airtight bags.

Uses of cement:

1. Used in construction prepares cement mortar.
2. To make RCC (Reinforced Cement Concrete)

Glass: Glass is hard, transparent, amorphous metallic silicate of different metals. Glass is called a super cooled liquid as molecules of glass are found moving very slowly like in extremely cold liquid. There are various types of glasses depending upon the component present in them. Some are:

Quartz glass: When silica is heated at 1600°C and allowed to cool slowly, it forms quartz glass. 

1. This glass is very hard and resistant to heat.
2. It is used to make electrical instruments, laboratory apparatus etc.

Water glass: When silicate is heated with Sodium Carbonate or Potassium Carbonate above 800°C, this glass is formed

SiO₂+ Na₂CO₃ →→ Na₂SiO₃+C0₂ (Heat)

SiO₂+ K₂CO₃ →→ K₂SiO₃+C0₂ (Heat)

1. This glass is soluble in water so it’s called water glass:
2. It is used to make fire proof materials, silica garden etc.

Ordinary glass (soda glass): When silica is heated with glass, Sodium carbonate, calcium carbonate and glass pieces at 850°C, this glass is formed. It is the most common type.

Annealing: The process of cooling almost ready glass wares slowly during their production is called annealing. It makes them resistant to temperature. It makes them resistant to temperature.

2SiO₂+ Na₂CO₃ + CaCO₃ →→ Na₂SiO₃CaSiO₃+2C0₂ (Heat)

Hard glass or potash lime glass:  When silica is heated white with potassium carbonate and calcium carbonate it fuses to form Hard glass. It has high melting point and can withstand high temperature.

2SiO₂+ K₂CO₃ + CaCO₃ →→ K₂SiO₃CaSiO₃+2C0₂ (Heat)

It is used in making hard glass test-tube laboratory Apparatus etc

Borosilicate glass: When silicate is heated with sodium carbonate, calcium carbonate and boric oxide, the mixture fuses to form borosilicate glass. It is also called pyrex glass. This glass is resistant to chemical and heat.

5SiO₂+ Na₂CO₃ + CaCO₃+ B₂CO₃ →→ Na₂SiO₃ CaSiO₃ B₂(SiO₃)+2C0₂ (Heat)

Used to make laboratory apparatus, kitchen ware etc.

Lead crystal glass: When silica is heated with potassium carbonate and lead monoxide, lead crystal glass is formed. This glass has high refractive index

2SiO₂+ K₂CO₃ + PbO →→ K₂SiO₃ PbSiO₃+C0₂ (Heat)

It is used to make apparatus like lenses, glass slab, prism etc.

Colored glass: The glass made colored by mixing different metal oxide in molten glass. Some examples

Ceramics: It is special type of clay used to make cups, plates, tiles, bricks etc. Its chemical name is hydrated aluminum silicate (Al₂O₃ SiO₂ H₂O)

Pure white clay used to make cup plate etc is called Kaolin or china clay.

Production of different materials from ceramics

1. The clay is grinded into powder and mixed with water to form thick paste.

2. It is given different shape according to need on a potter’s wheel.

3. It is dried in sun and heated in kilns.

4. It is cooled with tin oxide or lead oxide and then again heated. This process is called glazing. Glazing makes the object smooth shiny, non-porous and attractive.

5. Now, they are painted with different color and art and sent into market.

Properties of ceramics products

1. They are resistant to chemical, high temperature, bad conductor of heat and electricity.
2. They are not affected by acid, salt or water.

Polymers ond Plastics

Polymers is an extremely large molecule consisting of chain of small molecules called monomer. The process of farming polymer by joining the monomers nerves is called polymerization.

n(CH₂= CH₂)  →→  CH₂ – CH₂ — CH₂ – CH₂ (Polythene) ( under Polymerization)

Example of natural polymers: Protein, cellulose, silk etc

Example of synthetic polymers: plastic, nylon, terylene etc

Plastics: Plastic is a synthetic polymer which can be moulded to any shape when they are warm. There are 2 types of plastics

A) Thermoplastic: A plastic which becomes soft on heating and hard on cooling is called thermoplastic. It can be moulded again and again into various shapes. Eg, polythene, PVC, polystyrene etc

Uses

1. Polythene used to make bags, pipes etc
2. PVC  (Polyvinyl chloride) used to make pipes.
3. Poly styrene used to make thermacote.

B) Thermosetting plastic: Plastic which are hard and strong and are resistant to heat are called thermosetting plastic It can’t be moulded again into different shape. Eg, Bakelite, melamine etc

Bakelite: This plastic is obtained by polymerization of carbolic acid (C₆H₅O_H) and formal dehyde (HCHO). It is used to make handle of cooking utensils, housing of radio, TV, switches etc.

Melamine: It is used to make cup, plates, glasses etc.

Advantages of plastic:

1. It is waterproof, not affected by chemicals.
2. They are cheap and light so they’re easily portable.
3. They are found in different colors and looks attractive.

Disadvantages of plastic:

1. They are non bio-degradable, so they cause environmental pollution for long time.
2. When we burn plastics, it produces harmful gases that damage health of living organism as well as environment.

Q. Write 2 differences between thermoplastic and thermosetting plastic.

Soap: Sodium Potassium salt of higher fatty acids are called soap. For eg. Sodium palmitate. Soap can be obtained by heating animal fat or vegetable oil with Sodium hydro oxide.

C₃H₅COOCR₃ (fats/oil) + 3NaOH →→ 3NaCOOCR (soap) + C₂H₅(OH)₃ (glycerol)

where R: C₁₇H₃₅

1. Soap is used for cleaning.
2. It can not be used with hard water, as it form scum.
3. It is bio-degradable.

Detergent: Sodium salt of long chain benzene sulphonic acid are called detergent. Eg, Sodium lauryl sulphate (C₁₂H₂₅SO₄^–Na⁺)

1. Detergents are called soapless soap.
2. It can be used with hard and soft water.
3. It is better cleaning agent than soap.
4. It is not biodegradable.

Fertilizers: Substances that are added into soil in order to supply nutrients necessary for plant growth are called fertilizers.

There are 2 types of fertilizers:

1. Organic fertilizers (Compost)
2. Inorganic fertilizers (Chemical)

Organic fertilizers: Fertilizers that are prepared by decomposition of plant parts, dead bodies of animals or their waste is called organic fertilizers: Eg compost manure, animal dung, green manure. Role of organic fertilizers:

1. It supplies all the nutrients necessary for plant growth.
2. They are environmental friendly.
3. It improves the natural quality as well as water absorbing capacity of soil.

Inorganic fertilizers: Fertilizers that are prepared in industries by using various chemicals are called chemical fertilizers. There are mainly 3 types of chemical fertilizers:

Nitrogen fertilizer

Eg, Urea (NH₂-CO-NH₂), Ammonium Sulphate (NH₄)₂SO₄, Ammonium Nitrate (NH₄NO₃)

Plants need Nitrogen for the formation of protein, formation of chlorophyll and for their normal growth.

Phosphorus fertilizer

Eg, Ammonium Phosphate  (NH₄)₃PO₄ Sulphur phosphate [Ca(H₂PO₄) 2CaSO₄]

Plants need Phosphorus for growth of their root to assist in cell division and development of buds.

Potassium fertilizer

Eg, Potassium Chloride (KCl), Potassium sulphate (K₂SO₄), Potassium Nitrite (KNO₃)

Plants need Potassium to increase their immunity power and to assist in formation of protein.

NPK fertilizer

It is a special complete fertilizer prepared by mixing Nitrogen, Phosphorus and Potassium in right quantity as required by the plants. It is beneficial for farmers.

Insecticides: These are poisonous chemicals that are used for destroying or killing harmful insects some examples of insecticides are: 

Organic insecticides – DDT (Dichlorodiphenyl trichloro ethane), BHC (Benzene hexachloride) Baygon, Turmeric etc.

Inorganic insecticides – Calcium Arsenic, lime sulphur, lead Arsenate etc.

Advantages of insecticides

1. It is only a effective way to increase food production by destroying harmful insects (pests) that destroy crops.
2. It helps in control of diseases.

Disadvantages of insecticides

1. Where we use insecticides without precautions, it directly affects health of user and environment.
2. Insecticide also kills useful bacteria present in soil.
3. They are main cause of environmental pollution.
4. Food grown using insecticides are not healthy and is likely to cause various problems in our body.

Fibre: Fibre are thread-like strong materials which are used for making clothes, rope, net etc. There are 2 types d fibre:

1. Natural fibre
2. Artificial fibre

Natural fibre: The fibre that are formed from plants and animals are called natural fibre. For eg, silk, cotton, wool etc.

Artificial (synthetic) fibre: Fibre that are prepared by human are called synthetic fibre. Eg nylon, rayon etc

Chemical Pollution: Environmental degradation due to the various chemicals that are used in our daily life is called chemical pollution.

Causes of chemical pollution

1. Excess use of chemical fertilizers, insecticides, pesticides etc is the main cause of chemical pollution.
2. Harmful gases and various wastes released from industries, factories also cause chemical pollution.
3. Smoke from vehicles also causes chemical pollution.
4. Lack of proper management of plastic wastes and burning of plastic is also a cause of chemical pollution.
5. Various non-edible chemicals used as a coloring matter in food items are also the case of chemical pollution.

Control measures of chemical pollution.

1. Decrease in use of fossil fuel and increase in use of electric energy.
2. Reuse, recycle of various wastes like plastic help in controlling chemical pollution.
3. Decrease in use of chemical fertilizers, insecticides etc with suitable alternatives.
4. Increase in public awareness about the effect of chemical pollution help to control it.

Solid waste management

1. Reduction in generation of solid waste.
2. Reuse and recycle of waste materials.
3. Generation of energy.
4. Production of compost manure.
5. Incineration.
6. Land filling.