C/100=md/ms => md=c*ms/100=5,82*200/100=11,64g NaOH
o parte din apa din solutie va reactiona cu Na-ul introdus.
23g...18g.......40g
Na + H2O -> NaOH + 0,5H2
4,6g..x=3,6g....y=8g
msinitial=md+mH2O => msinitial-md=mapa=200-11,64=188,36g apa
masa de apa finala=188,36-3,6=184,76g
mNaOH=11,64+8=19,64g
msf=mNaOH+mapafinala=19,64+184,76=204,4
cf=mNaOH*100/msf=19,64*100/204,4=9,60%