Question

Aluminum can react with oxygen gas to produce aluminum oxide $\left(A{l}_2{O}_3\right)$ What type of reaction is this?

Answer 1

Answer
This is a synthesis reaction.
Explanation:We're given that aluminum (Al) can react with oxygen gas $(O_2$ don't forget it's diatomic!) to produce aluminum oxide $\left(A{l}_2{O}_3\right)$
The balanced chemical equation for this reaction is
$4Al\left(s\right)+3O_2\to 2A{l}_2{O}_3\left(s\right)$
A reaction in which two or more reactants combine to form only one product is called a synthesis reaction.
Here, there are two reactants (Al and O2) combining to form one product, Al2O3 (key word one), so this is a synthesis reaction.
Here is a useful image with more synthesis reaction examples: