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प्रश्न
How can the rate of the chemical reaction, namely, decomposition of hydrogen peroxide be increased?
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उत्तर
\[\ce{\underset{peroxide}{\underset{Hydrogen}{2H2O}_{2(l)}} -> \underset{water}{2H2O} + \underset{oxygen}{O2\uparrow}}\]
- The decomposition of hydrogen peroxide (H2O2) into water and oxygen takes place slowly at room temperature.
- However, hydrogen peroxide decomposes rapidly in the presence of manganese dioxide (MnO2) powder, which acts as a catalyst.
- Thus, by adding manganese dioxide (MnO2) powder, the rate of a chemical reaction can be increased.
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संबंधित प्रश्न
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- Take a plastic mug. Drill two holes at its base and fit rubber stoppers in these holes. Insert carbon electrodes in these rubber stoppers as shown in the following Fig.
- Connect these electrodes to a 6 volt battery.
- Fill the mug with water such that the electrodes are immersed. Add a few drops of dilute sulphuric acid to the water.
- Take two test tubes filled with water and invert them over the two carbon electrodes.
- Switch on the current and leave the apparatus undisturbed for some time.
- You will observe the formation of bubbles at both the electrodes. These bubbles displace water in the test tubes.
- Is the volume of the gas collected the same in both the test tubes?
• Once the test tubes are filled with the respective gases, remove them carefully. - Test these gases one by one by bringing a burning candle close to the mouth of the test tubes.
Caution: This step must be performed carefully by the teacher.
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- Which gas is present in each test tube?

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