sulfuric acid
Sulfuric acid is one of the strongest, most widely used, and most important inorganic acids in the global chemical industry.
With the chemical formula H₂SO₄, it is a colorless, odorless, oily liquid that is highly corrosive and readily soluble in water, releasing a large amount of heat upon dissolution.
Chemical Structure
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Molecular Formula: H₂SO₄
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Structure: Consists of two hydrogen atoms (H⁺) and one sulfate ion (SO₄²⁻), in which sulfur is centrally bonded to four oxygen atoms.
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Type of Bond: Both covalent and ionic, depending on the solvent environment.
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In aqueous solution, sulfuric acid fully dissociates, releasing two protons (H⁺).
Physical and Chemical Properties
| Property | Value / Description |
|---|---|
| Physical State | Clear, oily, colorless liquid |
| Density (at 98%) | ~1.84 g/cm³ |
| Boiling Point | 337 °C |
| Freezing Point | 10.4 °C |
| Solubility in Water | Very high (highly exothermic and dangerous) |
| pH (1% solution) | < 1 (extremely acidic) |
| Corrosivity | Very high — attacks metals, skin, and fibers |
| Flash Point | None (non-flammable but a strong oxidizer) |
Major Applications of Sulfuric Acid
Chemical and Petrochemical Industries
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Production of chemical fertilizers (phosphates, sulfates)
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Manufacturing of phosphoric acid, sulfonation, and pigments
Battery Industry
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Used as an electrolyte in lead-acid batteries (automotive and industrial)
Detergent and Cosmetic Industries
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Production of surfactants, such as alkylbenzene sulfonates
Metallurgical and Mining Industries
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Pickling of steel, and extraction of copper and zinc
Pharmaceutical and Laboratory Applications
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Used as a catalyst and dehydrating agent in chemical synthesis
Advantages of Sulfuric Acid
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Extremely strong acidity
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Low cost and wide industrial availability
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Versatile across numerous industrial processes
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High hygroscopicity (effective drying agent)
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Stable under proper storage conditions (in compatible containers)
Disadvantages and Limitations
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Highly hazardous to skin, eyes, and the respiratory system
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Exothermic reaction with water — requires great caution during dilution
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Reacts violently with metals, bases, and combustible organic materials
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Difficult handling and transportation — requires strict safety standards
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Environmental risk if spilled or improperly disposed of
sulfuric acid
| Products | Chemical formula | CAS number | Grade | Solubility in water | Vapor pressure | Melting point | Density (at 20°C) | Physical appearance |
|---|---|---|---|---|---|---|---|---|
| (Sulfuric Acid) | H₂SO₄ | 7664-93-9 | Industrial, laboratory (ACS), battery grade, ultrapure grade | Completely soluble (vigorous exothermic reaction with water) | 0.001 mmHg در 25°C | 10.3°C | 1.84 g/cm³ (for 98% w/w acid) | Clear, colorless to slightly yellow, oily, and thick liquid |






