S

Sodium hydroxide

IUPAC: sodium hydroxide

NaOH Bases & Alkalis CAS 1310-73-2
Expert Written | Fact Checked | Sources Cited | AllChemicals Editorial Team
Quick Reference
Formula / NotationNaOH
CAS Number1310-73-2
Molecular Weight39.997
Melting Point604 °F (USCG, 1999)
Boiling Pointgreater than 266 °F at 760 mmHg (USCG, 1999)
Density1.5 at 68 °F (USCG, 1999) - Denser than water; will sink
Solubility111 % (NIOSH, 2024)
AppearanceSodium hydroxide solution appears as a colorless liquid. More dense than water. Contact may severely irritate skin, eyes, and mucous membranes. Toxic by ingestion. Corrosive to metals and tissue.
Also Known As1310-73-2; Caustic soda; Sodium hydrate; Aetznatron; Soda lye; White caustic; Soda, caustic; Natriumhydroxid; Rohrputz; Plung
CategoryBases & Alkalis

What is Sodium hydroxide?

Sodium hydroxide (NaOH) is a base or alkali that appears as Sodium hydroxide solution appears as a colorless liquid. More dense than water. Contact may severely irritate skin, eyes, and mucous membranes. Toxic by ingestion. Corrosive to metals and tissue.. It has a molecular weight of 39.997 g/mol. Boiling point: greater than 266 °F at 760 mmHg (USCG, 1999). Melting point: 604 °F (USCG, 1999).

Formula & Notation

NaOH

IUPAC Name: sodium hydroxide

Other Names / Synonyms: 1310-73-2; Caustic soda; Sodium hydrate; Aetznatron; Soda lye; White caustic; Soda, caustic; Natriumhydroxid; Rohrputz; Plung

Properties & Characteristics

Appearance: Sodium hydroxide solution appears as a colorless liquid. More dense than water. Contact may severely irritate skin, eyes, and mucous membranes. Toxic by ingestion. Corrosive to metals and tissue.. Molecular formula: HNaO. Molecular weight: 39.997 g/mol. Boiling point: greater than 266 °F at 760 mmHg (USCG, 1999). Melting point: 604 °F (USCG, 1999). Density: 1.5 at 68 °F (USCG, 1999) - Denser than water; will sink. Solubility: 111 % (NIOSH, 2024). Vapor pressure: 0 mmHg (approx) (NIOSH, 2024).

Physical Data

PropertyValue
Melting Point604 °F (USCG, 1999)
Boiling Pointgreater than 266 °F at 760 mmHg (USCG, 1999)
Density1.5 at 68 °F (USCG, 1999) - Denser than water; will sink
Molecular Weight39.997
Solubility111 % (NIOSH, 2024)
AppearanceSodium hydroxide solution appears as a colorless liquid. More dense than water. Contact may severely irritate skin, eyes, and mucous membranes. Toxic by ingestion. Corrosive to metals and tissue.

Uses & Applications

Used in chemical manufacturing, pH adjustment, saponification, water treatment, and as a laboratory reagent.

Safety Information

Corrosive or irritant. Causes burns to skin and eyes. Store away from acids. Wear protective gloves and goggles. Consult SDS before use.

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

Key Facts

Term Sodium hydroxide
Formula NaOH
CAS Number 1310-73-2
Molecular Weight 39.997
Category Bases & Alkalis
Synonyms 1310-73-2; Caustic soda; Sodium hydrate; Aetznatron; Soda lye; White caustic; Soda, caustic; Natriumhydroxid; Rohrputz; Plung

Frequently Asked Questions

Sodium hydroxide (NaOH) is a base or alkali that appears as Sodium hydroxide solution appears as a colorless liquid. More dense than water. Contact may severely irritate skin, eyes, and mucous membranes. Toxic by ingestion. Corrosive to metals and tissue.. It has a molecular weight of 39.997 g/mol. Boiling point: greater than 266 °F at 760 mmHg (USCG, 1999). Melting point: 604 °F (USCG, 1999).

More "S" Terms

View all "S" terms →
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Editorial standards: Chemical data is sourced from peer-reviewed literature, CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA, and IAEA. For educational purposes only — always consult official SDS documentation and qualified professionals before handling chemicals.