Răspuns:
Explicație:
-se afla md sol. de NaOH
m=c.ms :100
md=20 .300 :100=60g NaOH
60g xg yg
2 NaOH + FeCl2 = 2NaCl + Fe(OH)2
2.40g 127g 90g
x=60. 127 :2 .40=95,25 g FeCl2
n=95,25g : 127g/moli=0,75moli FeCl2
y=60.90 :80=67,5 g
n=67,5g : 90g/moli=0,75 moli Fe(OH)2
MNaOH=23+16+1=40---->40g/moli
MFeCl2=56 +71=127----->127g/moli
MFe(OH)2=56 +2.16 +2=90---->90g/moli