Question

How would you balance the following equation: aluminium + oxygen gas$\to$ aluminium oxide?

Answer 1

Hint: As we know that a balanced equation is that in which the stoichiometric coefficient of a reactant is equal to that of the product. In order to balance the equation, we must make sure that both sides of the reaction that is reactant as well as product side have equal numbers of atoms. We must try to balance the oxygen atoms first, and then the other atoms later.

Complete answer:
- We will balance the equation: aluminium + oxygen gas$\to$ aluminium oxide as : $4Al+3{{O}_{2}}\to 2A{{l}_{2}}{{O}_{3}}$. Let us discuss about the steps to balance this chemical equation:
- As we are being described with the equation:
$Al+{{O}_{2}}\to A{{l}_{2}}{{O}_{3}}$ -In order to balance the equation, we will first balance the equation by achieving a common 6 oxygen atoms on either sides of the equation. So, we can write the equation as:
$Al+3{{O}_{2}}\to 2A{{l}_{2}}{{O}_{3}}$
- Now, as we can see here that there are 1 and 4 aluminium atoms present on each side. so, we will change the coefficient of the aluminium present on the reactant side to 4. Hence, we can write the balanced chemical equation as:
$4Al+3{{O}_{2}}\to 2A{{l}_{2}}{{O}_{3}}$
- Hence, we can conclude that we can balance the given equation: aluminium + oxygen gas$\to$ aluminium oxide as $4Al+3{{O}_{2}}\to 2A{{l}_{2}}{{O}_{3}}$.

Note:
- We should note that while balancing the reaction, we cannot change the molecular formula of the compound. That’s why when we are adding a number in the place of a stoichiometric coefficient, we are not changing the molecular formula of the compound.