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Grade 11Physical Chemistry

The weight of hypo ( Na2S2O3.5H2O ) is required to make 100 cm^3 of 0.2 N solution for use in the reaction , 2S2O3^2- + I2 S4O6^2- + 2I^- will be

Profile image of Sumit Kumar
9 Years agoGrade 11
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1 Answer

Profile image of Vikas TU
9 Years ago
From the reaction,
2S2O3^2- + I2 ========>>>>>>>   S4O6^2- + 2I^-
The valence factor for S => (2.5 – 2)*2 = > 1
From the equivalent concept,
moles os S2O3^2- => 0.2*100*1/1000 => 0.02
Hence the moles of Na2S2O3.5H2O = > 0.02
Weight = > 0.02*248 = 4.96 gms