Final answer:
The elements that are unbalanced in the equation CH₄ + O₂—> 2H₂O + CO₂ are C, H, and O. To balance the equation, we need to adjust the coefficients of the reactants and products.
Step-by-step explanation:
Based on the given equation CH₄ + O₂—> 2H₂O + CO₂, the elements that are unbalanced are C, H, and O. To balance the equation, we need to adjust the coefficients of the reactants and products so that the number of each element is the same on both sides of the equation.
Starting with C, we have 1 carbon atom on the left side and 1 carbon atom on the right side, so it is balanced.
Next, looking at H, we have 4 hydrogen atoms on the left side and 4 hydrogen atoms on the right side, so it is also balanced.
Finally, for O, we have 2 oxygen atoms on the left side and 4 oxygen atoms on the right side, which means O is unbalanced.
To balance the equation, we can multiply the coefficient of O₂ by 2 to get 4 oxygen atoms on both sides:
CH₄ + 2O₂—> 2H₂O + CO₂
Now, all the elements (C, H, and O) are balanced in the equation.