Question

84,75 mL solutie HCl de concentratie 36,5% si densitate ro=1,18 g/cm cub se dilueaza cu apa pana la o concentratie de 25 % . Care este masa de apa necesara dilutiei?

Answer 1

ro=ms/V=>ms=84,75*1,18=100,005g HCl

C=md/ms*100 => md=C*ms/100=36,5*100,005/100=36,5g HCl

ms=md+mH2O=>mH2O=ms-md=100,005-36,5=63,498g

C=md/ms*100 => 25=36,5/36,5+mH2O*100 => 912,5+25mH2O=3650 -> 2737,5=25mH2O -> mH2O=109,5g

mH2O adaugat = 109,5-63,498=46g