Question

ch₄ + o₂ → co₂ + h₂o balance and determine the coefficients 1, 2, 1, 2; 2, 2, 2, 2; 2, 1, 2, 1; 1, 1, 1, 1

Explanation:

Step1: Balance Carbon

On the left, we have 1 C in $CH_4$. On the right, we have 1 C in $CO_2$. So carbon is balanced initially with coefficient 1 for $CH_4$ and 1 for $CO_2$.

Step2: Balance Hydrogen

On the left, $CH_4$ has 4 H. On the right, $H_2O$ has 2 H per molecule. So we need 2 $H_2O$ to balance H (since $2\times2 = 4$). Now the equation is $CH_4 + O_2
ightarrow CO_2 + 2H_2O$.

Step3: Balance Oxygen

On the right, $CO_2$ has 2 O and $2H_2O$ has $2\times1 = 2$ O, so total O on right is $2 + 2 = 4$. On the left, $O_2$ has 2 O per molecule. So we need 2 $O_2$ (since $2\times2 = 4$) to balance O. The balanced equation is $CH_4 + 2O_2
ightarrow CO_2 + 2H_2O$. The coefficients are 1 (for $CH_4$), 2 (for $O_2$), 1 (for $CO_2$), 2 (for $H_2O$).

Answer:

1, 2, 1, 2 (corresponding to $CH_4$, $O_2$, $CO_2$, $H_2O$)