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प्रश्न
A metal nitrate 'A' on heating gives a metal oxide along with evolution of a brown coloured gas 'B' and a colourless gas, which helps in burning. Aqueous solution of 'A' when reacted with potassium iodide forms a yellow precipitate.
- Identify 'A' and 'B'
- Name the types of the reactions involved in the above statement.
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उत्तर
The metal in compound A is lead (Pb).
Therefore, we can write
Reaction 1 as
\[\ce{2Pb(NO_3)_2->[\Delta] 2PbO + 4NO_2 + O_2}\]
Reaction 2:
\[\ce{Pb(NO_3)_2 + 2KI ->Pbl_2 + 2KNO_3}\]
Compound A - lead nitrate: \[\ce{Pb(NO_3)_2}\]
Compound B - nitrogen dioxide- NO2
Reaction 1 is thermal decomposition, whereas,
reaction 2 is double decomposition reaction.
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संबंधित प्रश्न
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Tick the most appropriate answer.
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