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प्रश्न
Changes in which new substances are formed are called ______ changes.
उत्तर
Changes in which new substances are formed are called chemical changes.
Explanation:
Chemical changes result in the formation of one or more new substances with different properties from the original.
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संबंधित प्रश्न
State whether the following statement is true or false. In case a statement is false, write the corrected statement.
Iron and rust are the same substances.
Write your observation and a balanced equation in the case of the following substances being heated.
Zinc carbonate.
Distinguish by dilute sulphuric acid.
Copper and magnesium?
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- Colour change
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- Evolution or absorption of heat
- Formation of a precipitate.
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Complete the table given below.
| Addition of dil. H2SO4 to zinc | Test for gas evolved |
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\[\ce{Na->Na+}\]
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(i) Decaying of wood
(ii) Burning of wood
(iii) Sawing of wood
(iv) Hammering of a nail into a piece of wood
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(a) Is this a physical or a chemical change?
(b) Can you prepare one acidic and one basic solution by using the products formed in the above process? If so, write the chemical equation involved.
Rusting of iron is ______.
Both CO2 and H2 gases are ______.
