md=9g C2H2O4
Vs=500mL=0.5L
MHOOC-COOH==>C2H2O4=2AC+2AH+4AO=2*12+2+64=90g/mol
sau
MHOOC-COOH*2H2O [acidul oxalic prin alte carti este luat anhidru sau cu 2 molecule de apa..] = 90 + 36= 126g/mol
Eg=M/2=126/2=63g
sau
Eg=M/2=90/2=45g
Cn=md/Eg*Vs=9/63*0.5=9/31.5=0.285 Eg/L
sau
Cn=md/Eg*Vs=9/45*0.5=9/22.5=0.4 Eg/L