Presupunem V=1L=1000cm3
ro(densitatea)=ms/V==>ms=ro*V=1.22g/cm3*1000cm3=1220g NaOH
CM=n/Vs==>n=Cm*Vs=6.1*1=6.1 moli NaOH
MNaOH=40g/mol
n=md/M==>md=n*M=6.1*40=244g NaOH
Cp=md/ms*100=244/1220*100=20%
B. 1000mL..............................244g NaOH
1mL.................................x=0.244g NaOH
C. ms=400g
md=244g
Cp=md/ms*100=244/400*100=61%
C este fals
D. trebuie sa faci cu regula dreptunghiului..
100%.........................40g=m1
x=62.5%....................25g=m2
m1/m2=40/25=8/5 ==> este fals
E. 100%..................5g
50%...................50g
m1/m2=5/50=1/10==?>