Question

Do 250g roztworu 15% NaOh dodano 20g tego zwiazku ,jakie jest Cp tego zwiakzku?

Answer 1

Mr=250g
cp=15%
ms1=20g
cp2=?
cp=ms*100%/mr
ms=cp*mr/100%=15%*250g/100%=37,5g
mr2=mr+ms1=250g+20g=270g
ms2=ms+ms1=37,5g+20g=57,5g
cp2=ms2*100%/mr2=57,5g*100%/270g=21,3%

Answer 2

Z def. stęż.procent.
15g ------100g roztworu
xg--------250g roztworu
x=15*250/100
x=37,5g
dodaję 20g,więc
57,5g------270g(250g+20g)
xg----------100g
x=21,3g
x=21,3%

Answer 3

Witaj
dane mr1=250g, cp1=15%, ms2=20g,
szukane cp2
masa subst, rozp.w roztw.pocz. ms1 = mr1*cp1/100% = 250g*15%/100%=37,5g
po dodaniu ms2 = 20g całkowity ms = ms1 + ms1 = 37,5g + 20g = 57,5g
całkowit masa roztworu mr = mr1 + ms2 = 250g + 20g = 270g

końcowe cp2 = ms*100%/mr = 57,5g*100%/270g = 21,3%

.................pozdrawiam