Humber Admissions Practice Test

What occurs during a displacement reaction?

1. A single compound breaks down

2. Two elements combine to form a single element

3. One element replaces a similar element in a compound

4. Multiple reactants combine to form one product

The correct answer is: One element replaces a similar element in a compound

In a displacement reaction, one element replaces a similar element in a compound. This type of reaction typically occurs between a more reactive element and a less reactive element in a compound, resulting in the formation of a new compound and the release of the replaced element. For example, in the reaction between zinc and hydrochloric acid, zinc displaces hydrogen from the hydrochloric acid to form zinc chloride and hydrogen gas. This illustrates how the replacement process works, highlighting the essential characteristic of displacement reactions: the replacement of one element by another. This understanding of displacement reactions is crucial in various fields, including chemistry and materials science, as it helps predict the outcomes of reactions and the reactivity of different elements and compounds.