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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
Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.
\[\ce{NH3_{(g)} + HCl_{(g)} -> NH4Cl_{(s)}}\]
FILL IN THE BLANK
The new substances formed during a chemical reaction are called the ..................
True or false
New substances are formed in a chemical change.
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Higher order Thinking question
A very hot glass on putting in cold water cracks. What does this change indicate?
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Write word equations for two chemical reactions with the help of materials given in the box.
| Air, copper sulphate, iron, vinegar, iron oxide, carbon dioxide, iron sulphate, copper, lime water, water |
