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प्रश्न
What is meant by a chemical reaction? Explain with the help of an example.
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उत्तर
A chemical reaction is the process in which atoms of some elements rearrange, that is, undergo a chemical change, to form a new product with different properties. This involves breaking old bonds between the reacting atoms and making new chemical bonds between the rearranged atoms.
For example, the burning of magnesium ribbon in air. In this reaction, magnesium ribbon, on heating, combines with oxygen to form a white powder of magnesium oxide, which has properties entirely different from those of magnesium and oxygen.
\[\ce{2Mg_{(s)} + O2_{(g)} ->[heat] 2MgO_{(s)}}\]
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