Page 93 - Chemistry_Form_2

Chemistry
for Secondary Schools

Types of chemical reactions
Task 4.3

Use library books and reliable online resources to explore various chemical
reactions which occur in everyday life, and classify each one based on its reaction
FOR ONLINE READING ONLY
type.

Chemical reactions drive numerous everyday processes, such as cooking, energy
production, plant growth, and digestion. These reactions convert raw materials
into essential products that support life and modern living. The following are the
types of chemical reactions, along with their real-life applications.

Combination (synthesis) reactions
A combination reaction is a chemical reaction in which two or more chemical
species combine to form a single product. Combination reactions are also referred
to as synthesis reactions. This type of reaction is expressed in the form of:

A + B AB

Generally, there are three types of combination reactions, namely a reaction
between two or more elements, reaction between elements and compounds, and
reaction between two compounds.

Combination reaction between two elements
This reaction occurs when two elements combine to give a single compound. An
example of a combination reaction between two elements is when magnesium
burns in air (oxygen) with a bright white flame to form white solids of magnesium
oxide. Figure 4.1 shows the burning of magnesium in oxygen.

Activity 4.2

Aim: To burn magnesium in oxygen

Requirements: A pair of tongs, heat source (Bunsen burner), gas jar, lighter,
magnesium ribbon, oxygen source, and steel wool
Procedure
1. Clean about 0.1 g of a piece of magnesium ribbon by using steel wool.

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