The degree of dissociation of HI at a particular temperature is 0*8. Calculate the volume of2 MNa_(2)S_(2)O_(3) solution required to neutralize the iodine present in the equilibrium mixture of a reaction when 2 mole each of H_(2) and I_(2) are heated in a closed vessel of 2 litre capacity.

The degree of dissociation of HI at a particular temperature is 0*8. C

1.	The degree of dissociation of HI at a particular temperature is 0*8. Calculate the volume of2 MNa_(2)S_(2)O_(3) solution required to neutralize the iodine present in the equilibrium mixture of a reaction when 2 mole each of H_(2) and I_(2) are heated in a closed vessel of 2 litre capacity.
Answer» Solution :Degreeof disociation of `HI (alpha) = 08` `{:(,2 HI,hArr,H_(2),+,I_(2)),("Before dissociation",1,,0,,0),("Moles after disso",1-alpha,,alpha//2,,alpha//2):} ` `K_(c) = ((alpha//2)(alpha//2))/(1 -alpha)^(2) = alpha^(2)/(4(1 -alpha)^(2) )=(08)/(4(1-08)^(2))= 4` Step 2. Calculation of `I_(2)`in equilibrium MIXTURE. ` {:(,H_(2),+,I_(2),hArr,2 HI),("Intial moles",2,,2,,0), ("Moles after reaction ",(2-x),,(2-x),,2x//2), ("Molar conc.",(2-x)//2,,(2-x)//2,,2x//2):}` `K'_(c)= 1/K_(c)-(2x//2)^(2)/(((2-x)/2)((2-x)/2))=(4x^(2))/(2-x)^(2)` ` :. (4x^(2))/(2-x)^(2) = 1/4 or (2x)/(2-x) =1/2 or x=2/5 ` Thus, `I_(2) "left" = 2 - 2/5 = 8/5"mole. "` Step 3. Calculation of VOLUME of hypo solution used . `2 Na _(2) S_(2) O_(3) + I_(2) to Na_(2) S_(4) O_(6) + 2 Nal ` ` :. "Moles of " N_(2)S_(2)O_(3)" reacted " = 2 xx 8/5 "mole" = 16/5 "mole " ` Volume of 2 M ` Na_(2)S_(2) O_(3) " reacted " = 1000/2 xx 16/5 = 1600 "mL " = 16 L`