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Question
What happens when zinc granules are treated with dilute solution of H2SO4, HCl, HNO3, NaCl and NaOH Also write the chemical equations if reaction oçcurs.
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Solution
- With dilute H2SO4: Hydrogen gas evolves -
`"Zn"("s") + "H"_2"SO"_4 ("dil".) -> "ZnSO"_4("aq") + "H"_2("g")` - With dilute HCl: Hydrogen gas evolves -
`"Zn"("s") + 2"HCl" ("dil".) -> "ZnCl"_2("aq") + "H"_2("g")` - With dilute HNO3: Nitrous oxide gas evolves. It is colourless.
`4"Zn"("s") + 10"HNO"_3("aq") -> 4"Zn"("NO"_3)_2("aq") + 5"H"_2"O"("l") + "N"_2"O"("g")` - With NaCl : There is no chemical reaction, with NaOH : Hydrogen gas evolves:
`"Zn"("s") + 2"NaOH"("aq") -> underset("Sod. Zincare")("Na"_2"ZnO"_2("aq")) + "H"_2("g")` - NaOH solution
Zn(s) + 2 NaOH (aq) → Na2ZnO2(aq) + H2
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