13)
la 60 gr.C
ms=468,66g 148g sol.....48g sare
468,66.......x=152g(md)
se depun y g cristalohidrat
MCh=278
278g ch...............152g sare
y g ch..................152y/278
la 20 gr.C
ms=468,66g -y
md=152-152y/278
md/ms= ( 152-152y/278 )/
(468,66g -y )=22/122
==> y=......
mie mi-a dat 184,17g deci raspunsul ar fi a)
14)
200g oleum
contin 40g SO2 si 160g H2SO4
200g sol H2SO4 contin 20g H2SO4 si restul apa
200g oleum + 200g solH2SO4==> 400g sol ce contint:
-160g H2SO4 din oleum;
-20g H2SO4 din solutia 10%
-
49g H2SO4 din reactia SO2+H2O=H2SO4
Total: 229g H2SO4 (md)
c=229*100/400=57,25 %
