The Alkali Metals, Halogens, and Noble Gases
This page introduces three important groups of elements in the periodic table: alkali metals, halogens, and noble gases. Each group has unique characteristics and chemical behaviors.
Alkali Metals
The alkali metals include lithium, sodium, potassium, rubidium, cesium, and francium. These elements are highly reactive and readily form positive ions.
Highlight: Chemical properties of group 1 elements include high reactivity and a tendency to lose electrons, making them strong reducing agents.
Vocabulary: Reducing agents are elements that donate electrons to other elements, reducing them to their elemental form.
Halogens
The halogen group consists of fluorine, chlorine, bromine, iodine, and astatine. These elements are also highly reactive but tend to gain electrons to form negative ions.
Definition: Halogens are strong oxidizing agents, meaning they readily accept electrons from other elements.
Alkali Metal-Halogen Reactions
When alkali metals react with halogens, they form compounds called salts through ionic bonding.
Example: The reaction between sodium and chlorine produces sodium chloride, commonly known as table salt.
Highlight: Exothermic reactions between alkali metals and halogens are often accompanied by flame or light emission due to the large amount of heat released.