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Chemical reaction and equation

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  Chemical Reaction:  The transformation of chemical substance into another chemical substance is known as Chemical Reaction. For example: Rusting of iron, the setting of milk into curd, digestion of food, respiration, etc. In a chemical reaction, a new substance is formed which is completely different in properties from the original substance, so in a chemical reaction, a chemical change takes place. Only a rearrangement of atoms takes place in a chemical reaction. ·          The substances which take part in a chemical reaction are called reactants. ·          The new substances produced as a result of a chemical reaction are called products. Example:  The burning of magnesium in the air to form magnesium oxide is an example of a chemical reaction. 2Mg(s) + O 2 (g)  △ →  2MgO(s) Before burning in air, the magnesium ribbon is cleaned by rubbing with sandpaper. This is do...
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Magnetic effect of current - Class 10

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  Magnet:   Magnet is an object that attracts objects made of iron, cobalt and nickle. Magnet comes to rest in North – South direction, when suspended freely. Use of Magnets:  Magnets are used ·          in refrigerators. ·          in radio and stereo speakers. ·          in audio and video cassette players. ·          in children’s toys and; ·          on hard discs and floppies of computers. Properties of Magnet ·          A free suspended magnet always points towards the north and south direction. ·          The pole of a magnet which points toward north direction is called north pole or north-seeking. ·          The pole of a magnet ...
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