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प्रश्न
Explain by writing a word equation.
Hard water gets softened on mixing with a solution of washing soda.
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उत्तर
To soften the hard water, a solution of washing soda is added to it. This results in a chemical reaction to form a precipitate of insoluble carbonate salts of calcium and magnesium. As the dissolved salts of calcium and magnesium go out in the form of a precipitate of the carbonate salts, the water is softened. The following equation can be written for this chemical change.
Word equation:
Calcium chloride + Sodium carbonate `→` Calcium carbonate + Sodium chloride
Chemical equation (unbalanced):
CaCl2 + Na2CO3 → CaCO3 + NaCl
संबंधित प्रश्न
Write a short note on the information derived from a balanced chemical equation.
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Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
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State the original colour of the following substance and colour of residue obtained after heating.
Copper carbonate
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Sodium Sulphide
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- Colour change
- Effervescence or gas evolved
- Evolution or absorption of heat
- Formation of a precipitate.
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Complete the table given below.
| Heat on copper carbonate | Test for gas evolved |
State the following reaction represent oxidation or reduction.
\[\ce{Ag->Ag+}\]
Classify the following as physical or chemical properties
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Can you change rust back into iron by some simple method?
