Proccentna koncentracija rastvora

teodora99's picture

Izracunaj procentnu koncentraciju rastvora koji nastaje mesanjem 500g 5% rastvora NaCl, 500g 10% rastvora NaCl i 500g H2O??

milicaradenkovic's picture

mr1=500 g w1= 5% w2=10% a mr2=500 g i m(vode)=500 g

ms1=w1*mr1=500*0.05=25 g  NaCl

ms2=mr2*w2=0.1*500=50 g NaCl

mru=ms1+ms2+m(vode)=50+25+500=575 g

msu=ms1+ms2=50+25=75 g NaCl

wu.=msu/mru=75/575=0.13=13 % NaCl