Question

question 3 (1 point)
the coefficient of o₂ in the balanced version of ch₄ + o₂ → co₂ + h₂o is
1
2
3
4

Explanation:

Step1: Balance the carbon atoms

The un - balanced equation is \(CH_4+O_2
ightarrow CO_2 + H_2O\). There is 1 carbon atom on the left (in \(CH_4\)) and 1 carbon atom on the right (in \(CO_2\)). So, the carbon atoms are already balanced.

Step2: Balance the hydrogen atoms

There are 4 hydrogen atoms in \(CH_4\) on the left. On the right, in \(H_2O\), there are 2 hydrogen atoms. To balance the hydrogen atoms, we put a coefficient of 2 in front of \(H_2O\). The equation becomes \(CH_4+O_2
ightarrow CO_2+2H_2O\).

Step3: Balance the oxygen atoms

On the right - hand side, in \(CO_2\) there are 2 oxygen atoms and in \(2H_2O\) there are \(2\times1 = 2\) oxygen atoms. So, in total, there are \(2 + 2=4\) oxygen atoms on the right. On the left - hand side, in \(O_2\), let the coefficient be \(x\). Since each \(O_2\) molecule has 2 oxygen atoms, \(2x\) oxygen atoms are on the left. Setting \(2x = 4\) (for oxygen balance), we get \(x = 2\). The balanced equation is \(CH_4 + 2O_2=CO_2+2H_2O\).

Answer:

B. 2