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प्रश्न
A chemical reaction is generally accompanied by certain external indications or characteristics. These include – change of – (a) colour (b) state (c) smell (d) evolution of gas (e) formation of precipitate (f) evolution or absorption of heat. With reference to change of colour – state the change in colour seen when the following are heated – zinc carbonate.
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उत्तर
Change of colour — In certain chemical reactions a change of colour is seen to be observed. Heat on substances to observe change in colour of reactants and products.
Heat on:
Zinc carbonate ZnCO3 → ZnO + CO2 [g]
Colour change:
Zinc carbonate [ZnCO3] – White – to Zinc oxide [ZnO] – Yellow (when hot)
APPEARS IN
संबंधित प्रश्न
Balance the given equation:
HNO3 + Ca(OH)2 
Ca(NO3)2 + H2O
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- Ammonia
- Sulphur dioxide
- Hydrogen Chloride
- Chlorine
- Carbon Dioxide
- Oxygen
- Hydrogen
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(c)Select acidic gases from the gases mentioned in Q.1 (a). How is the acidic nature suspected?
(d) State the gas responsible for bleaching action.
(e)Which gas turn blue cobalt chloride paper light pink?
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Al + H2O → Al2O3 + H2
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