The document is about rocks, minerals and metals. It discusses the different types of rocks like igneous, sedimentary and metamorphic rocks and how they are formed. It also describes the most common minerals found in the Earth's crust like oxygen, silicon, aluminum, iron etc. and lists some important minerals and their uses. Finally, it explains the extraction of iron from its ore in a blast furnace.

1. © PRADIP PATEL ASIA SCIENCE Std:- VIII Rocks, Minerals, and Metals Graphics & Written By :- Pradip B. Patel Asia English School 1,sunrise park, opp, Drive in road Theltej Ahmedabad – 38 00 54

2. Chapter -3 Rocks, Minerals and Metals qDko, qinjo Ane 2atuAo SHALE LIMESTONE SANDSTONE FOLDED ROCK FORMATION GAS WATER OIL Rocks are found on the crust of the earth and made up of mineral IRON ROCK © PRADIP PATEL

3. Some are coarse grained as granite. Clay has much fine grains that we cannot see them separately. If you closely examine a piece of granite, you will find that it is made up of a number of substances under a magnifying lens or a microscope. Substances which assemble together to form rocks are called minerals . Minerals are naturally occurring inorganic substances. Std - 8 th chapter – 3 Rocks, Minerals & Metals © PRADIP PATEL Magnifying lens

4. © PRADIP PATEL 1.0 2.1 2.6 2.8 3.6 5.1 8.2 27.8 46.8 OXYGEN ( O 2 ) SILICON ( Si ) ALUMINIUM ( Al ) IRON ( Fe ) CALCIUM ( Ca ) SODIUM ( Na ) POTASSIUM ( K ) MAGNESIUM ( Mg) OTHERS The Earth’s Crust The average thickness of earth crust is 35 km under the continents and 10 km under the oceans. Three forth of the earth crust is made just of two non metals. (1) Oxygen (2) Silicon. Remainder of the crust consists of mainly six metals (1) Aluminum (most abundant) (2) Iron (3) Calcium (4) Sodium (5) Potassium (6) Magnesium. Std - 8 th chapter – 3 Rocks, Minerals & Metals Minerals Percentage

5. © PRADIP PATEL Pressure Weathering, erosion and sedimentation Deep burial pressure and high heat for melting SEA Metamorphic Rocks Sedimentary Rocks Igneous Rocks Std - 8 th chapter – 3 Rocks, Minerals & Metals Magma Heat, pressure & chemical changes Melts, cools and becomes solid Heat,pressure & chemical change Weathering, erosion and becomes solid

6. © PRADIP PATEL IGNEOUS ROCKS Magma Meaning :- Word derived from the latin word ‘ignis’ meaning fire. First rock to appear on the earth’s surface. Formation :- Formed by the cooling and solidification of extremely hot molten material, magma below the earth crust. This magma pushes its way through earth’s crust with high pressure to form igneous rocks. Large part of west central part of our country called the Decean Plateau . Granite is formed when the rising magma solidifies before reaching the surface in the form of coarse grained. Std - 8 th chapter – 3 Rocks, Minerals & Metals

8. © PRADIP PATEL PRESSURE METAMORPHIC ROCKS HEAT & PRESSURE FORMATION :- When igneous or sedimentary rocks are subjected to intense heat, compression or fluid injection the physical & chemical properties changes which results in metamorphic rock Std - 8 th chapter – 3 Rocks, Minerals & Metals

10. © PRADIP PATEL Non-metallic minerals and their uses Std - 8 th chapter – 3 Rocks, Minerals & Metals Mineral Uses 1 Quartz Glass, Sandpaper, Telephone, Radio, Watches. 2 Feldspur Porcelain, China dishes. 3 Mica Insulator in Electrical appliances: irons, motors, toasters 4 Rock salt In food, food preservation, raw material for chemical industry. 5 Gypsum Cement, Plaster of paris 6 Talc Talcum powder 7 Pitch blend Nuclear fuel 8_ Monazite Nuclear fuel for breeder reactor.

11. © PRADIP PATEL Std - 8 th chapter – 3 Rocks, Minerals & Metals Identify uses of mineral High Strength Salt

12. © PRADIP PATEL Some common ores Std - 8 th chapter – 3 Rocks, Minerals & Metals Chemical formula Metal Type of ore Haematite Fe 2 O 3 Iron Oxide Iron Pyrite FeS 2 Iron Sulphide Copper Pyrite CuFeS 2 Copper Sulphide Copper glance Cus / Cu 2 S Copper Sulphide Bauxite Al 2 O 3 . 2H 2 O Aluminium Oxide Galena PbS Lead Sulphide Litharge PbO Lead Oxide Pyrolusite MnO Manganese Oxide

13. © PRADIP PATEL Waste gas SLAG Calcium silicate MOLTEN IRON BLAST FURNACE 300 0 C. 500 0 C. 700 0 C. 900 0 C. 1000 0 C. 1200 0 C. 1900 0 C Cone & Glass shape HOT AIR Middle portion of the furnace is known as BOSCH . its width is about 7-8 meters. Blast furnace total height is about 30-40 meters. Out side portion is made up of steel , and inside portion is lined with fire bricks. FeO + CO  Fe + CO 2 Iron oxide, limestone & coke CaCO 3 heat CaO + CO 2 CaO + SiO 2  CasiO 3 Impurities slag Fe 2 O 3 + C  2 Fe 3 O 4 + CO Fe 3 O 4 + CO  3 FeO + CO 2 Std - 8 th chapter – 3 Rocks, Minerals & Metals

14. © PRADIP PATEL Pig iron & Wrought iron Std - 8 th chapter – 3 Rocks, Minerals & Metals Pig iron Wrought iron It contains 4 to 5 percent carbon and other impurities such as sulphur, phosphorous, silicon and manganese. It is the purest commercial form of iron free from carbon. The presence of impurities lowers the melting point. It is malleable. It is brittle. It is ductile and stronger. It can be melted and moulded into various shapes such as pipes, storage tanks, bath-tubes, stores, cylinder and other shapes. It can not used for molded articles. Sheets and wires cannot be made of pig iron. It can be hammered into sheets and drawn into wire or given desired shapes.

15. © PRADIP PATEL Waste gas Iron oxide, lime stone& coke Hot air . SLAG This way molten iron is directly taken to steel plants. The concentrated ore along with coke (c) and limestone are added to a blast furnace. Blasts of hot air at about 1900 0 C are blown into the furnace lined with fire bricks. The coke reduces the ore to metallic iron. The molten iron collects at the bottom of the furnace. Limestone on heating decomposes to calcium oxide and carbon dioxide. Calcium oxide reacts with the sand and forms a slag (calcium silicate) 300 0 C. 500 0 C. 700 0 C. 900 0 C. 1000 0 C. 1200 0 C. 1900 0 C BLAST FURNACE Std - 8 th chapter – 3 Rocks, Minerals & Metals

16. 2o.- Ð p/kr` -Ë qDko,qinjo Ane 6atuAo © PRADIP PATEL Impure copper anode Impurities Copper sulphate solution Electric supply + - iv·<t ivwajn4I kaœprnu> xuµIkr` kaœprne kaœpr sLfe3na µav`ma> 2n6/uv trIke levama> Aave 0e Jyare xuµ kaœprnI p¤IAone 1`2/uv trIke levama> Aave 0e. iv·<t p/vah p/sar krva4I 2n6/uv Aog5e 0e Ane xuµ kaœprna Aayno 1`2/uv trf jay0e Ane Tya> jma 4ay 0e. ANy AxuiµAo §av`na ti5ye wegI 4ay 0e. Pure copper cathode