Question

reaction occurs when one compound reacts and is broken down into different elements or
combustion
decomposition
single replacement
synthesis

Explanation:

To determine the correct reaction type, we analyze each option:

• Combustion: Involves a substance reacting with oxygen, usually producing heat and light (e.g., burning fuel), not breaking down a compound into simpler parts.
• Decomposition: A reaction where a single compound breaks down into two or more simpler substances (elements or compounds). This matches the description "one compound reacts and is broken down into different elements or [compounds]".
• Single Replacement: One element replaces another in a compound (e.g., \( A + BC

ightarrow AC + B \)), not breaking down a compound into simpler parts.

• Synthesis: Involves combining simpler substances to form a more complex compound (e.g., \( A + B

ightarrow AB \)), the opposite of decomposition.

Answer:

decomposition