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प्रश्न
Explain by writing a word equation.
Limestone powder disappears on adding to dilute hydrochloric acids.
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उत्तर
Limestone is predominantly Calcium carbonate(CaCO3). When calcium carbonate reacts with a 10% solution of HCl. Then Calcium chloride is formed as a salt along with water and carbon dioxide gas (brisk effervescence).
2HCl + CaCO3 → CaCl2 + CO2 +H2O
In this reaction, we add hydrogen ions (H+), which will react with the carbonate ion [\ce{(CO^{2-}_3)}\] to form hydrogen carbonate \[\ce{(HCO^-_3)}\] ions, which are soluble in water and the limestone will dissolve.
संबंधित प्रश्न
Fill in the blank:
The substances formed as a result of a chemical reaction are called _______
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Close contact
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Two solids combine to form a liquid
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| Column I | Column II | ||
| 1. | Burning of coal | a. | Rusting |
| 2. | Painting of a surface | b. | Evaporation |
| 3. | Dipping iron in the water | c. | Chemical change |
| 4. | Salt from seawater | d. | Prevention of rusting |
Define the following term:
Chemical change
