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Question
Starting from zinc how would you obtain hydrogen using a dilute acid.
[Give balanced equation & name the product formed in the case other than hydrogen].
Name a metal which will not react with the reactants above to give hydrogen.
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Solution
With dil. acids: Metals like Zn, Fe, Pb form corresponding salt.
\[\ce{Zn + dil.2HCl -> \underset{\text{Zinc chloride}}{ZnCl2 + H2}}\]
\[\ce{Fe + H2SO4 -> \underset{\text{Ferrous sulphte}}{FeSO4 + H2}}\]
\[\ce{Pb + 2HCl dil. ->\underset{\text{Lead chloride}}{PbCl2 + H2}}\]
Cu and metals below Cu do not react with dil. acids.
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