Alkali metals

Definition

Alkali metals are a group of elements in Group 1 of the periodic table, known for their high reactivity and tendency to form +1 ions. These metals include lithium, sodium, potassium, rubidium, cesium, and francium.

5 Must Know Facts For Your Next Test

1. Alkali metals have a single electron in their outermost shell.
2. They are highly reactive, especially with water, forming hydroxides and releasing hydrogen gas.
3. Alkali metals are soft and can be cut with a knife; they also have low melting points compared to most other metals.
4. These elements readily form ionic compounds by losing their one valence electron to achieve a stable noble gas configuration.
5. They exhibit characteristic colors when burned: lithium produces a red flame, sodium yields a yellow flame, and potassium creates a lilac flame.

Review Questions

• What is the common charge of ions formed by alkali metals?
• Why do alkali metals react vigorously with water?
• Which alkali metal would you expect to have the lowest melting point?

Related terms

Periodic Table: A tabular arrangement of chemical elements organized by increasing atomic number and groups based on similar chemical properties.

Ionic Bond: A type of chemical bond that forms between oppositely charged ions due to electrostatic attraction.

Valence Electron: An outermost electron of an atom that participates in chemical bonding.