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Alkali Metals

Group 1: Li, Na, K, Rb, Cs, Fr; ns¹ valence
Quick Reference
Formula / NotationGroup 1: Li, Na, K, Rb, Cs, Fr; ns¹ valence
Also Known AsGroup 1 metals; Group IA metals; ns¹ metals; lithium group metals

What is Alkali Metals?

The alkali metals are the six elements in Group 1 (IA) of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). They all have one electron in their outermost s-orbital and are the most reactive metals, readily losing this electron to form +1 cations. They react vigorously with water to produce hydrogen gas and metal hydroxide.

Formula & Notation

Group 1: Li, Na, K, Rb, Cs, Fr; ns¹ valence

Other Names / Synonyms: Group 1 metals; Group IA metals; ns¹ metals; lithium group metals

Properties & Characteristics

Soft, silvery-white metals; low density and melting point; Group 1 / ns¹ electron configuration; most reactive metals; always form +1 ions; react with water: 2M + 2H₂O → 2MOH + H₂; reactivity increases down the group; store under mineral oil or argon

Uses & Applications

Sodium in street lamps (Na vapour lamps); lithium batteries (Li-ion cells); sodium hydroxide (NaOH) manufacture; potassium in fertilisers; rubidium in atomic clocks; caesium in photoelectric cells; lithium in psychiatric medications

Safety Information

Extremely reactive — react violently with water producing flammable H₂ gas and caustic hydroxides. K, Rb, Cs can ignite spontaneously in air. Store under mineral oil or dry inert gas. Never use water to extinguish alkali metal fires (use dry sand). Wear full PPE.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Alkali Metals
Formula Group 1: Li, Na, K, Rb, Cs, Fr; ns¹ valence
Synonyms Group 1 metals; Group IA metals; ns¹ metals; lithium group metals

Frequently Asked Questions

The alkali metals are the six elements in Group 1 (IA) of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). They all have one electron in their outermost s-orbital and are the most reactive metals, readily losing this electron to form +1 cations. They react vigorously with water to produce hydrogen gas and metal hydroxide.

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