Single Replacement Reactions

Single replacement reactions, also known as single displacement reactions, occur when one element replaces another in a compound. This type of reaction follows the general form:

A + BC → AC + B

Where A and B are elements, and BC is a compound. During the reaction, A replaces B in the compound BC to form a new compound AC and free element B.

Key Concepts

• Reactivity Series: The reactivity series is a list of metals in order of their reactivity, from most reactive to least reactive. This series helps predict whether a single replacement reaction will occur.
• Activity Series: The activity series is a list of non-metals in order of their reactivity, from most reactive to least reactive. This series also helps predict single replacement reactions.
• Observe the Reaction: Single replacement reactions can often be identified by observing a change in color, formation of a precipitate, or evolution of a gas.

Example

Let's consider the reaction between zinc (Zn) and hydrochloric acid (HCl):

Zn + 2HCl → ZnCl2 + H2

In this reaction, zinc replaces hydrogen in hydrochloric acid to form zinc chloride and hydrogen gas.

Study Guide

1. What is a single replacement reaction?
2. How can the reactivity series and activity series be used to predict single replacement reactions?
3. What are some observable signs that a single replacement reaction has occurred?
4. Provide an example of a single replacement reaction and explain the products formed.

Remember to practice writing and balancing single replacement reactions to solidify your understanding of this topic.