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प्रश्न
What do you observe when H2S is passed through a lead nitrate solution.
उत्तर
When gas is passed to lead nitrate solution it also turns black.
\[\ce{\underset{\text{(colourless)}}{Pb(NO3)2} + H2S -> \underset{\text{(Black)}}{PbS} + 2HNO3}\]
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