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What is chemical reaction ?mention the characteristic of chemical reaction |
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Answer» The process in which new substances with new properties are formed from one or more substances Chemical reaction is the process in which new substance is formed Characteristic are 1 -evolution of gas 2- change in colour The characteristics of chemical reactions are : 1) Change of colour - When citric acid is added to Potassium permangenate then the purple colour starts discharging . 2)Change of state - When hydrogen(gas) reacts with oxygen(gas) , they form water a liquid 3)Evolution of a gas - When lead nitrate is heated the it decomposes to lead oxide , nitrogen dioxide with oxygen .4) Formation of a precipitate - When lead nitrate reacts with potassium iodide , it forms a yellow precipitate Lead iodide and potassium nitrate . 5)Change in temperature -- Exothermic reaction - reaction in which heat is released When quick lime reacts with water to form slaked lime , it releases a lot of energy . - Endothermic reaction - reaction in which heat is absorbed The process in which one or more substances react to form new substances. |
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