Răspuns:
1.
MZn=65g/mol
MO2=2x16=32g/mol
2x65g....32g
2Zn + O2 → 2ZnO
xg.........12,8g
x=12,8x2x65/32=calculeaza
2.
MCl2=2x35,5=71g/mol
MHCl=1+35,5=36,5g/mol
71g.............2x36,5g
H2 + Cl2 → 2HCl
142g..........xg
x=142x2x36,5/71=calculeaza
Explicație:
