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प्रश्न
A student wants to study a decomposition reaction by taking ferrous sulphate crystals. Write two precautions he must observe while performing the experiment.
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उत्तर
Precautions for the decomposition reaction of reffous sulphate crystals.
\[\ce{\underset{\text{(Light Green)Feffous sulphate crystals}}{FeSO4.7H2O} ->[\Delta] \underset{\text{(white)Anhydrous ferrous sulphage}}{FeSO4} ->[\Delta] \underset{\text{(Brown)Ferric Oxide}}{Fe2O3} + SO2 + SO3}\]
(1) The mouth of the boiling tube should not be at pointed.
(2) Waft gases are emitted from FeSO4 on heating . The gases SO2 and SO3 are very harmful , so deep breath should not be taken when smelling the odour of the gases .
(3) Test tube holder must be used while heating the test tube.
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संबंधित प्रश्न
Why is the amount of gas collected in one of the test tubes in the following Activity double of the amount collected in the other? Name this gas.
- 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.
- What happens in each case?
- Which gas is present in each test tube?
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- What is substance S? What is its clear solution known as?
- What is substance T? Name any two natural forms in which substance T occurs in nature.
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