Question

Urgent!!! Va rog, multumesc!

Answer 1

-1       +6                          0           +2

KI + H2SO4 --> K2SO4 + I2 + H2S + H2O  

   2x 2I⁻ _+2e-_> I⁰2  oxidare (ag. reducator, KI)

   1x  S⁶⁺_+4e-_> S²⁺ reducere (ag. oxidant, H2SO4)

M.KI = 39+127 = 166 g/mol

266g    n moli

  8KI + 5H2SO4 --> 4K2SO4 + 4I2 + H2S + 4H2O  

8x166       5

=> n = 266x5/8x166 = 1 mol H2SO4

stim ca Cm = n/Vs

=> Vs = n/Cm = 1/6 = 0,166 L sol. H2SO4