Răspuns:
Explicație:
2Na +2H2O=2NaOH +H2 a=Na b=NaOH
2NaOH + CuSO4= Na2SO4 + Cu(OH)2 c=Na2SO4 d=Cu(OH)2
3NaOH + FeCl3=3 NaCl + Fe(OH)3 e= Fe(OH)3 f=NaCl
2NaCl + 2H2O =2 NaOH + H2 + Cl2
Bazele : NaOH , Cu(OH)2 , Fe(OH)3
3moli xmoli
2Na +2 H2O =2NaOH +H2
2moli 2moli
x=3 .2 : 2=3moli Na
m= n . M
m= 3moli.23g/moli=69g Na
Comp. procentuala la Fe(OH)3
M=56+ 3.16 +3=107----->107g/moli
107g------------56gFe-------48g O-------3gH
100g--------------x----------------y--------------z
x=100.56: 107=
y=100.48: 107=
z=100.3: 107=
