Reduction: MnO4- + 8H+ + 5e- --> Mn2+ +
4H2O
Oxidation: C2O4 2- ---> 2CO2+
2e-
Combining (and balancing) the two half reactions yields:
2MnO4 2- + 5 C2O4 2- + 16H+ ---> 2Mn2+ + 10CO2 + 8
H2O
no of moles of Na2C2O4 = W/G.M.Wt
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= 0.1956/134Â Â = 0.00146 moles
from balanced equation
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5 moles of Na2C2O4 react with 2 moles of KMnO4
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0.00146 moles of Na2C2O4 react with = 2*0.00146/5 = 0.000584 moles
of KMnO4
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molarity = no of moles/volume in L
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0.02 = 0.000584/volume in L
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volume in L = 0.000584/0.02 = 0.0292 L = 29.2ml >>>>
answer
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