Răspuns:
Explicație:
300g sol. NaOH , c= 20%
react. cu HCl
masa de HCl cons.
-se afla md sol. de NaOH
md= c.ms : 100
md= 20 . 300 : 100 = 60g NaOH
60g xg
NaOH + HCl= NaCl + H2O
40g 36,5g
MNaOH= 23 + 16 +1=40-------> 40g/moli
MHCl= 1 + 35,5= 36,5----> 36,5g/moli
x= 60 . 36,5 : 40 = 54,75 g HCl
n= m : M
n= 54,75g : 36,5g/moli =1,5 moli HCl