H2SO4 +2NaOH=2H2O +Na2SO4
M H2SO4 =98
M 2H2O = 36
M Na2SO4 =142
M 2NaOH= 80
c=md/ms ×100
md =c×ms/100
md =20×25/100
md =5g H2SO4 pur
X =80×5/98
X=400/98
X=4,081 g NaOH
Y=4,081×36/80
Y=1,836 g 2H2O
Z=1,836×142/36
Z=7,242 g Na2SO4
Rezulta 9,078 g.
36g H2O.......... 1mol
1,836 g H2o..... a moli
a=1,836/36
a=0,051 moli H2O
142g Na2SO4........ 1mol
7,242 g Na2SO4.... b moli
b=7,242/142
b=0,051 moli Na2SO4
Rezulta 0,102 moli în total.
