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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 – lead [IV] oxide.
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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:
Lead [IV] oxide 2PbO2→2PbO + O2 [g]
Colour change:
Lead [IV] oxide [PbO] – Brown – to Lead monoxide [PbO] – Yellow.
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संबंधित प्रश्न
Balance the given equation:
H2O2 
H2O + O2
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(a) law of conservation of momentum
(b) law of conservation of mass
(c) law of conservation of motion
(d) law of conservation of magnetism
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What is the colour of this precipitate? Name the compound precipitated.
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four product
Write a balanced equation for the following word equation:
Aluminium + Oxygen → Aluminium oxide
What are reactants? Explain with the help of example.
