W(NaCl)=1.966g/58.5g/mol=0.0341mol
v(NaCl)=1.966g*2.17g/ml=4.267ml
v(H2O)=200-4.267=195.733ml/1000=0.195733 L
Cм=0.0341mol/0.195731L=0.174mol/L=0.174M
H2O+SO3=H2SO4 -соединение
4Li+2H2O=4LiOH -соединение
30,14г хг
2Ba + O2 -> 2BaO
274г 306г
х=30,14*306/274=33,66г