Question

Se supun electrolizei 117 NaCl de concentratie 20 % baza rezultata se trateaza cu o substanta de acid sulfuric de concentratie 49 % si densitatea 1,4 g/
ml.
calculeaza:
a) nr de molecule de baza rezultata
b) concentratia proncentuala a bazei formata in urma electrolizei .
c) volumul solutiei de acid sulfuri folosit.

Answer 1

20% din 117=0,2*117=23,4g sare
117g.......................2*Na
2NaCl + 2H2O -> 2NaOH + H2 + Cl2
23,4g........................x=?
x=0,4*Na=0,4*6,0225*10^23=2,409*10^23molecule
mNaOH=0,4*Na*40/Na=16g
mapasolutie=117-23,4=93,6g
msf=16+93,6=109,6g solutie
%soda=16*100/109,6≈14,6%
2*40g..........98g
2NaOH + H2SO4 -> Na2SO4 + H2O
16g..............t=?
t=16*98/80=19,6g
ms=md*100/c=19,6*100/49=40g solutie
d=ms/Vs => Vs=ms/d=40/1,4=28,57ml acid sulfuric