International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

In the reaction X + ZSO₄ → XSO₄ + Z, what type of reaction is taking place?

1. Synthesis reaction

2. Decomposition reaction

3. Displacement reaction

4. Combustion reaction

The correct answer is: Displacement reaction

The reaction X + ZSO₄ → XSO₄ + Z is classified as a displacement reaction, also known as a single replacement reaction. In this type of reaction, one element (X in this case) displaces another element (Z) from a compound (ZSO₄) to form a new compound (XSO₄) and release the displaced element (Z). Displacement reactions typically occur when a more reactive element replaces a less reactive element in a compound. This transformation highlights the ability of elements to interact and form new products while releasing others, showcasing the dynamic nature of chemical compounds. In contrast, other types of reactions such as synthesis involve the combination of two or more substances to form a new compound, while decomposition reactions involve breaking down a single compound into its constituent parts. Combustion reactions typically involve a substance reacting with oxygen to produce energy and often generate heat and light. These distinctions clarify why this specific reaction is identified as a displacement reaction.