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प्रश्न
State the law of conservation of mass.
उत्तर १
Law of conservation of mass: It states that mass can neither be created nor destroyed in a chemical reaction. During any change (physical or chemical), matter is neither created nor destroyed. However it may change from one form to another.
Requirements: H-shaped tube called Landolt’s tube, Sodium chloride solution, silver nitrate solution, etc.
Procedure: A specially designed H-shaped tube is taken. Sodium chloride solution is taken in one limb of the tube and silver nitrate solution in the other limb as shown in figure.
Both the limbs are now sealed and weighed. Now the tubes is averted so that the solutions can mix up together and react chemically. The reaction takes place and a white precipitate of silver chloride is obtained.
\[\ce{\underset{\text{(silver nitrate)}}{AgNO3}+\underset{\text{(sodium cholride)}}{NaCl}->\underset{\text{(silver chloride)}}{AgCl↓}+\underset{\text{(sodium nitrate)}}{NaNO3}}\]
The tube is weighed again. The mass of the tube is found to be exactly the same as the mass obtained before inverting the tube.
Thus, this experiment clearly verifies the law of conservation of mass.
उत्तर २
The law states that during any chemical change, the total mass of the products is equal to the total mass of the reactants.
संबंधित प्रश्न
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Complete the statement by filling the blank with the correct word given below.
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| Law of conservation of mass | Sir William Crookes |
| Law of constant proportion | James Chadwick |
| Cathode rays | Joseph Proust |
| Anode rays | Lavoisier |
| Neutrons | Goldstein |
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