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प्रश्न
A solid substance P which is very hard is used in the construction of many buildings, especially flooring. When substance P is heated strongly, it decomposes to form another solid Q and a gas R is given out. Solid Q reacts with water with the release of a lot of heat to form a substance S. When gas R is passed into a clear solution of substance S, then a white precipitate of substance T is formed. The substance T has the same chemical composition as starting substance P.
- What is substance P? Write its common name as well as chemical formula.
- What is substance Q?
- What is gas R?
- 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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उत्तर
- Substance P is calcium carbonate. Its common name is limestone, and its chemical formula is CaCO3.
- Substance Q is calcium oxide (CaO).
- Gas R is carbon dioxide gas (CO2).
- Substance S is calcium hydroxide [Ca(OH)2]. Its clear solution is known as lime water.
- Substance T is calcium carbonate (CaCO3). Two natural forms of calcium carbonate are calcite and mollusc shell.
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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?
What type of chemical reaction is used to extract metals from their naturally occurring compounds like oxides or chlorides?
What type of chemical reaction take place when lime-stone is heated?
Explain the following type of chemical reaction, giving two examples for it:
Decomposition reaction
Identify the type of following reaction :
How can the rate of the chemical reaction, namely, decomposition of hydrogen peroxide be increased?
Give a balanced equation for –
A thermal decomposition reaction involving heat on limestone [calcium carbonate]
Give a balanced equation for –
An electrolytic decomposition reaction involving a neutral liquid
Differentiate between the following:
Thermal decomposition and thermal dissociation.
Explain the reaction given in the figure.
Chemical volcano is an example of ______ type of reaction.
Which one of the following processes involves chemical reactions?
Give the ratio in which hydrogen and oxygen are present in water by volume.
Which of the following is an endothermic process?
Assertion: Decomposition of vegetable matter into compost is an endothermic reaction.
Reason: Decomposition reaction involves breakdown of a single reactant into simpler products.
Balance the following chemical equation and identify the type of chemical reaction.
`"HgO"("s") overset("(heat)")(->) "Hg"("l") + "O"_2("g")`
Complete the following reaction:
\[\ce{C_12H_22O11->[Heat]}\] ______ + ______.
A metal nitrate 'A' on heating gives a metal oxide along with evolution of a brown coloured gas 'B' and a colourless gas, which helps in burning. Aqueous solution of 'A' when reacted with potassium iodide forms a yellow precipitate.
- Identify 'A' and 'B'
- Name the types of the reactions involved in the above statement.
