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2010-03-12T19:53:51+01:00
1. Cp=(Cm * M*100%)/d roztworu

Cm=0,5 mol/dm3
d=1.04g/cm3=1040g/dm3

Cp= (0.5 mol/dm3*78 g/mol*100%)/1040 g/dm3= 3.75 %


2.Cm=?
V=200 cm3=0.2 dm3
Cm=n/V

n=m/M
n=0.73 g/36,5=0.02 mole

Cm=0.02 mole/0.2 dm3= 0.1 mol/dm3
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2010-03-12T20:00:43+01:00

Cm = 0,5mol/dm3
d=1,04g/cm3 = 1040g/dm3
M Na2S = 46+32= 78g/mol
Cp= ms/mr *100%
ms=Cp*mr/100%
Cm= ms/M*Vr
ms= Cm*M*Vr
Cp=Cm*M*Vr*100%/mr
Cp= Cm*M*100%/d
Cp = 0,5 mol/dm3 * 78g/mol * 100% ÷ 1040g/dm3 = 3,75%

Zad 2
ms= 0,73g
Vr = 200cm3 = 0,2 dm3
M HCl = 36,5g/mol
Cm = ms/ M*Vr
Cm= 0,73g/0,2 dm3*36,5g/mol = 0,1 mol/dm3
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