October 5, 2025

What Is A Single Displacement Reaction

Q: What is the difference between a single and double-displacement reaction?

In a single-displacement reaction, one element replaces another in a compound. In a double-displacement reaction, the positive and negative ions of two different ionic compounds switch places, forming two new compounds.

Q: Does a single-displacement reaction always happen when an element and compound are mixed?

No. The reaction only proceeds if the lone element is more reactive than the element it would displace in the compound, as determined by the activity series.

Q: Are single-displacement reactions always redox reactions?

Yes, they are a type of oxidation-reduction (redox) reaction. The element that is displaced is reduced (gains electrons), and the element that does the displacing is oxidized (loses electrons).

Q: Can non-metals participate in single-displacement reactions?

Yes. For instance, a more reactive halogen (like chlorine) can displace a less reactive halogen (like bromine or iodine) from a salt solution. Example: Cl₂(g) + 2NaBr(aq) → 2NaCl(aq) + Br₂(l).

Learn about single-displacement reactions, where one element replaces another in a compound. Includes a clear definition, key principles, and examples.

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Defining a Single-Displacement Reaction

A single-displacement reaction, also known as a single-replacement reaction, is a type of chemical reaction where a more reactive element displaces a less reactive element from a compound. In essence, one element trades places with another element within a compound.

Section 2: The General Formula

The general form of this reaction can be written as A + BC → AC + B. In this formula, element A reacts with compound BC. If A is more reactive than B, it will displace B, forming a new compound AC and leaving element B by itself.

Section 3: A Practical Example

A classic example is when a piece of zinc metal is placed in a solution of copper(II) sulfate. The zinc is more reactive than the copper, so it displaces the copper to form zinc sulfate and solid copper. The balanced chemical equation is: Zn(s) + CuSO₄(aq) → ZnSO₄(aq) + Cu(s).

Section 4: The Role of the Activity Series

To predict if a single-displacement reaction will occur, chemists use an 'activity series.' This series ranks elements based on their reactivity. An element can only displace another element from a compound if it is higher on the activity series. This principle is fundamental for predicting reaction outcomes and is applied in areas like metallurgy and electrochemistry.

Frequently Asked Questions

What is the difference between a single and double-displacement reaction?

Does a single-displacement reaction always happen when an element and compound are mixed?

Are single-displacement reactions always redox reactions?

Can non-metals participate in single-displacement reactions?