Question

$CH_4+O_2\Rightarrow \:CO_2+H_2O$

Answer 1

$\mathrm{Balance}\:CH_4+O_2\Rightarrow \:CO_2+H_2O:\quad CH_4+2O_2\Rightarrow \:CO_2+2H_2O$

$\mathrm{Balance\:reaction\:by\:inspection}$

$CH_4+O_2\Rightarrow \:CO_2+H_2O$

$C\:\mathrm{is\:balanced}$

$CH_4+O_2\Rightarrow \:CO_2+H_2O$

$\mathrm{To\:balance}\:H\:\mathrm{multiply}\:H_2O\:\mathrm{on\:the\:right\:by}\:2$

$CH_4+O_2\Rightarrow \:CO_2+2H_2O$

$\mathrm{To\:balance}\:O\:\mathrm{multiply}\:O_2\:\mathrm{on\:the\:right\:by}\:2$

$CH_4+2O_2\Rightarrow \:CO_2+2H_2O$

Answer 2

Answer

$\mathrm{Balance\:reaction\:by\:inspection}$

$\sf CH_4+O_2\Rightarrow \:CO_2+H_2O$

$\sf C\:\mathrm{is\:balanced}$

$\sf CH_4+O_2\Rightarrow \:CO_2+H_2O$

$\mathrm{\sf To\:balance}\:H\:\mathrm{multiply}\:H_2O\:\mathrm{on\:the\:right\:by}\:2$

$\sf CH_4+O_2\Rightarrow \:CO_2+2H_2O$

$\mathrm{To\:balance}\:O\:\mathrm{multiply}\:O_2\:\mathrm{on\:the\:right\:by}\:2$

$\sf CH_4+2O_2\Rightarrow \:CO_2+2H_2O$