Respuesta :

I believe the answer is  can be elements or compounds
In this case, elements in the decomposition reaction is the substance that cannot be separated into simpler substances.
Compounds, technically act as a reactant in the decomposition reaction, but since the reaction breakdown one substance into two or more, sometimes it exists in the product.

Answer:

can be elements or compounds.

Explanation:

A decomposition reaction occurs when one compound origin two or more compound, or when it breaks and form its elements. For example:

2NaN₃(g) → 3N₂(g) + 2Na(s)

It was formed a compound (N₂) and an element (Na).