Odpowiedź:
1. 36g 2. 0,05 mol 3. 2,44 mol/dm3
Wyjaśnienie:
1. mr=300g
Cp=12%
Cp=ms/mr *100%
ms=Cp*mr/100%
ms=12%*300g/100%=36g
2.
Cn=0,2mol/dm3
v=250cm3=0,25dm3
Cn=n/v
n=Cn*v=0,2mol/dm3*0,25dm3=0,05 mol
3.
Masa KOH=56g
v1=250cm3=0,25dm3
Cn1=3mol/dm3
Cn2=1,5mol/dm3
v2=150cm3=0,15dm3
n1=Cn1*v1=3mol/dm3*0,25dm3=0,75 mol
n2= 1,5mol/dm3*0,15dm3=0,225mol
nc=n1+n3=0,75mol +0,225 mol =0,975 mol
vc=v1+v2=0,25dm3+0,15dm3=0,4dm3
Cc=nc/vc=0975mol/0,4dm3=2,44mol/dm3
