Answer 1 :-
We need to balance the equation
[tex]\sf \bullet\quad H_2 + O_2 \longrightarrow H_2O [/tex]
By adding 2 moles of [tex]\sf H_2 [/tex] on the both sides
[tex]\sf \bullet \quad 2H_2+O_2 \xrightarrow{\;By\:balancing\;} H_2O[/tex]
Hence, balanced !
