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प्रश्न
Study the following figure and answer questions.
a) After heating Calcium carbonate, which gas is formed in a test tube?
b) When we pass this gas through limewater what change, did you observe?
c) Write down the chemical reaction showing the product formation after heating the Calcium carbonate.
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उत्तर
a) carbon dioxide
b) lime water turns milky. 
APPEARS IN
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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Give a scientific reason.
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\[\ce{2KClO3_{(s)} ->[Heat] 2KCl + 3O2_{(g)}}\]
Which of the following statement about the reaction is correct?
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- Write a balanced chemical equation of the reaction.
- Identify the brown gas X evolved.
- Identify the type of reaction.
- What could be the pH range of aqueous solution of the gas X?
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Answer the questions with the help of a diagram:
- What type of reaction does calcium carbonate undergoes?
- What change in colour is observed in lime?
- Write the chemical equation.
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Write one equation for the decomposition reaction where energy is supplied in the form of electricity.
