Question

hi friends how I balance CH4+O2---CO2 +H2O

Answer 1

CH4+2O2-----CO2+2H2O

Answer 2

LHS-RHS

1 C - 1 C
4 H-2 H
2 O- 3 O
So on right side 2 hydrogen are less and one oxygen is more..so
Balanced equation is
CH4+2O2==CO2 + 2H2O

hope this helps!