Page 94 - Chemistry_Form_2

Chemistry
for Secondary Schools

2. Hold the ribbon by using a pair of tongs and heat it over a Bunsen burner
or any heat source flame.
3. When it starts to burn, lower it into the gas jar of oxygen as shown in Figure 4.1.
Do not drop it into the jar.
FOR ONLINE READING ONLY

Figure. 4.1: Magnesium burning in oxygen

Questions

1. What is the colour of flame when magnesium is burned?

2. What is the balanced chemical equation associated with this experiment?

Combination reaction between elements and compounds
This occurs when an element reacts with a compound to form another compound.
For example, carbon monoxide gas reacts with oxygen gas to form carbon dioxide
gas.

Combination reaction between two compounds
Two compounds may react with each other to form a new compound. For
example, calcium oxide (quicklime) reacts with carbon dioxide gas to form
calcium carbonate (limestone).

Student’s Book Form Two 87

01/08/2025 11:20:59
CHEMISTRY FORM TWO NEW 2025 DUMMY.indd 87 01/08/2025 11:20:59
CHEMISTRY FORM TWO NEW 2025 DUMMY.indd 87