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प्रश्न
State what you would observe when the following substance is heated in a glass test tube Copper (II) carbonate Red lead .
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उत्तर
CuCO3 → CuO + CO2 ↑
The blue-green powder turns black and a colourless gas is evolved which extinguishes a burning flame.
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संबंधित प्रश्न
How do the following help in bringing about a chemical change?
catalyst .
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Reduction reaction is the exact opposite of
- displacement reaction
- decomposition reaction
- oxidation reaction
- none of these
FILL IN THE BLANK
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TRUE \ FALSE
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Balancing a chemical equation is based on
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A reaction involving
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(ii) formation of precipitate
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| Hydrogen | Oxygen | Carbon dioxide | Chlorine | |
| Litmus test | ||||
| Apply a burning splint to the gas | ||||
| Colour of gas | colourless | colourless | colourless | greenish-yellow |
| Odour of gas |
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