Properties - Sulphuric Acid
September 27, 2003

Introduction

Sulphuric acid is a colourless to amber, slightly cloudy, oily liquid with a specific gravity almost twice that of water.  At normal temperatures and a concentration of 98% or lower, it has little odour.  At higher temperatures and above a concentration of 98% irritating sulphur trioxide (SO3) fumes may be liberated.  Oleum (fuming sulphuric acid) is a colourless to white, heavy, oily liquid containing sulphur trioxide dissolved in sulphuric acid.  On exposure to air, oleum releases irritating white fumes of sulphur trioxide.

All grades of sulphuric acid have an affinity for water resulting in evolution of heat when diluted.  In the case of oleum, the reaction occurs with explosive violence.  Sulphuric acid and oleum will absorb moisture from the air resulting in dilution of the acid.  All grades are strongly corrosive and personal safety precautions should be carefully followed.

Many organic substances, wood, starch, sugar, paper, etc. are charred on contact with sulfuric acid, forming carbon.  Very small quantities of organic matter will blacken sulphuric acid as a result of suspended carbon.

Colour	Clear, colourless liquid Contaminants in the acid may impart a colour to the acid.
Reactivity	Sulphuric acid will attack many metals and in its concentrated form is a strong oxidizing agent and may cause ignition on contact with organic materials, nitrates, carbides, chlorates, etc.
Flash Point	None
Structure
Specific Gravity	Varies with concentration and temperature.   See Table  See Chart
Freezing Point	See Table  See Chart
Boiling Point	See Table  See Chart
Viscosity	See Chart
Conductivity	See Chart
Enthalpy	See Chart

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