Răspuns:
niu=V/Vm= 11,2/22,4 mol=0,5molH2
2mol.......2mol........2mol...........1mol
2Na + 2H2O---> 2NaOH + H2
x.................y.................z...............0,5mol
x= niu= 1molNa
m= niuxA,Na= 23g Na
solutia este formata din NaOH dizovat in restul de apa de la sfarsitul; reactiei
z=1molNaOH
m= niuxmiu=1x40g=40gNaOH
Y=niu=1mol
m=niuxmiu=1x18g=18gH2O
m,apa = roxv= 1x200g=200g
m,apa ramasa = 200g-18g= 182gH2O
C=mdx100/ms
md= 40g
ms= md+m,apa= 40+182=>222g
c= 40x100/222=18%
Explicație:
