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प्रश्न
Give one example each of which illustrates the following characteristics of a chemical reaction:
evolution of a gas
उत्तर
When Zinc reacts with dil. sulphuric acid. Hydrogen gas is evolved, with an effervescence
\[\ce{\underset{\text{zinc}}{Zn} +\underset{\text{dil.suphuric acid}}{H2SO4} -> \underset{\text{zinc sulphate}}{ZnSO4} + \underset{\text{hydrogen}}{H2}}\]
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संबंधित प्रश्न
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Three metal samples of magnesium, aluminium and iron were taken and rubbed with sandpaper. These samples were then put separately in test tubes containing dilute hydrochloric acid. Thermometers were also suspended in each test tube so that their bulbs dipped in the acid. The rate of formation of bubbles was observed. The above activity was repeated with dilute nitric acid and the observations were recorded.
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OR
Name the type of reaction on the basis of which the reactivity of metals is decided. You have two metals X and Y. How would you decide which is more reactive than the other?
