Răspuns:
Explicație:
200 g sol. HCl , c=40%
react. cu Na
g,moli NaCl
-se afla md sol. de HCl
md= c . ms : 100
md= 40 .200 : 100= 80g HCl
80g xg
2Na +2 HCl = 2NaCl + H2
2.36,5g 2.58,5g
x= 80 . 117 : 73 = 128,219 g NaCl
n= m : M
MNaCl= 23 + 35,5 =58,5------> 58,5g/moli
n= 128,219g : 58,5g/moli = 2,18moli NaCl
M HCl= 1+ 35,5=36,5-----> 36,5g/moli