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Question
Explain the reaction given in the figure.
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Solution
- Calcium carbonate undergoes a decomposition reaction in the first test tube forming calcium oxide powder and carbon dioxide gas.
\[\ce{\underset{\text{Limestone}}{CaCO_{3(s)}} ->[\Delta] \underset{\text{Calcium oxide}}{CaO_{(s)}} + \underset{\text{Carbon dioxide}}{CO2\uparrow}}\] - Carbon dioxide gas formed in the first test tube turns the lime water milky in the second test tube due to the formation of calcium carbonate, which is insoluble in water.
\[\ce{\underset{\text{Calcium hydroxide}}{Ca(OH)_{2(aq)}} + \underset{\text{Carbon dioxide}}{CO_{2(g)}} -> \underset{\text{Calcium carbonate}}{CaCO_{3(s)}} + \underset{\text{Water}}{H2O_{(l)}}}\] - The calcium oxide powder, remains behind in the first test tube.
RELATED QUESTIONS
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?
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MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
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- reactants
- water
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What does one mean by endothermic reaction? Give example.
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Identify the type of following reaction :
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Answer the following question.
2 g of silver chloride is taken in a china dish and the china dish is placed in sunlight for some time. What will be your observation in this case? Write the chemical reaction involved in the form of a balanced chemical equation. Identify the type of chemical reaction.
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\[\ce{2KClO3(s)->[\Delta] 2KCl(aq) + 3O2(g)}\]
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Give a balanced equation for the following type of reaction:
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Differentiate between the following:
Thermal decomposition and thermal dissociation.
Photolysis is a decomposition reaction caused by ______
Chemical volcano is an example of ______ type of reaction.
Which one of the following processes involves chemical reactions?
Which of the following is an endothermic process?
When SO2 gas is passed through a saturated solution of H2S, which of the following reaction occurs?
Balance the following chemical equation and identify the type of chemical reaction.
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Complete the following reaction:
\[\ce{C_12H_22O11->[Heat]}\] ______ + ______.
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When lead nitrate is heated strongly in a boiling tube, two gases are liberated and a solid residue is left behind in the test tube.
- Name the type of chemical reaction and define it.
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- Name the substance ‘X’ and write its formula.
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