Question

aluminum + oxygen yields aluminum oxide
write a balanced equation for this chemical reaction.
a al + o → alo
b al + o → al₂o₃
c 2al + 3o₂ → al₂o₃
d 4al + 3o₂ → 2al₂o₃

Explanation:

Step1: Check element counts in reactants and products

In a chemical - reaction, we need to balance the number of each type of atom on both sides of the equation. Aluminum (Al) and oxygen (O) are the elements involved. Oxygen in nature exists as $O_2$.

Step2: Analyze option A

In $Al + O
ightarrow AlO$, oxygen in nature is not $O$ but $O_2$, and the formula of aluminum oxide is incorrect. Aluminum has a + 3 oxidation state and oxygen has a - 2 oxidation state, so the correct formula of aluminum oxide is $Al_2O_3$.

Step3: Analyze option B

In $Al+O
ightarrow Al_2O_3$, oxygen is not in its correct elemental form ($O_2$) and the equation is not balanced.

Step4: Analyze option C

In $2Al + 3O_2
ightarrow Al_2O_3$, the number of oxygen atoms is not balanced. On the left - hand side, there are 6 oxygen atoms ($3\times2$ in $3O_2$), and on the right - hand side, there are 3 oxygen atoms in $Al_2O_3$.

Step5: Analyze option D

For $4Al+3O_2
ightarrow 2Al_2O_3$, on the left - hand side, there are 4 aluminum atoms and 6 oxygen atoms ($3\times2$ in $3O_2$). On the right - hand side, in $2Al_2O_3$, there are $2\times2 = 4$ aluminum atoms and $2\times3=6$ oxygen atoms. The equation is balanced.

Answer:

D. $4Al + 3O_2
ightarrow 2Al_2O_3$