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Question
A colourless lead salt, when heated, produces a yellow residue and brown fumes.
(a) Name the lead salt.
(b) Name the brown fumes.
(c) Write a chemical equation of the reaction involved.
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Solution
(a) Lead salt is lead nitrate.
(b) The brown fumes is nitrogen dioxide gas.
(c) The chemical reaction is given as follows:
2Pb(NO3)2 (s) → 2PbO (s) + 4NO2 (g) + O2 (g)
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