Question

which is a characteristic of a decomposition reaction?
substance p replaces x in the compound xy.
substance xyz breaks down into x, y, and z.
substance z burns in the presence of oxygen to form zo.
substance x combines with y to form compound xy.

Explanation:

A decomposition reaction is defined as a reaction where a single compound breaks down into two or more simpler substances. Let's analyze each option:

• The first option describes a single - replacement reaction (where one element replaces another in a compound).
• The second option: Substance XYZ (a single compound) breaks down into X, Y, and Z (simpler substances), which fits the definition of a decomposition reaction.
• The third option describes a combustion reaction (a substance reacting with oxygen).
• The fourth option describes a combination (synthesis) reaction (two substances combining to form a compound).

Answer:

Substance XYZ breaks down into X, Y, and Z.