Simple Acids (Strong Vinegar)

Simple acids, specifically concentrated acetic acid (often called “Strong Vinegar” or “Spirit of Vinegar”), are a step up from household vinegar. While normal vinegar is 5-8% acid, strong vinegar can reach much higher concentrations, making it useful for chemical reactions that weak vinegar cannot sustain.

Description of what it is like

A clear, colorless liquid with an overpowering, suffocating smell of vinegar. In very high concentrations (glacial acetic acid), it can freeze into ice-like crystals at cool room temperatures. It is corrosive to skin and many metals.

Origin and where to find it

• Not natural: Does not occur naturally in high concentrations.
• Source: Produced by processing standard vinegar.

Minimum processing required

1. Fractional Freezing (Jack separation):
   • Freeze a container of vinegar. Water freezes before acetic acid.
   • Discard the ice (which is mostly water).
   • The remaining liquid is concentrated acid.
   • Repeat multiple times to increase concentration.
2. Distillation:
   • Distill vinegar, but be careful as water and acetic acid have close boiling points. The first fraction is often water-rich.
   • Distilling metal acetates (like copper acetate) can yield very pure acid (historical method).

Tools needed to work on it

• Freezing container: For the freeze method (clay, wood, or metal that resists acid).
• Distillation apparatus: For the heat method (glass or ceramic retort).
• Storage bottles: Glass or ceramic with tight seals.

Common forms of use

• Solvent: Dissolving Copper to make Verdigris (pigment) or Lead to make White Lead (pigment).
• Cleaning: Removing heavy rust or scale.
• Medicine: Cauterizing wounds (historical).

Possible substitutes

• Sulfuric Acid: Much stronger, but harder to make.
• Citric Acid (concentrated): Lemon juice boiled down.
• Formic Acid: From distilling ants (historical).

Limitations and common failures

• Hygroscopic: Concentrated acid absorbs water from the air, weakening itself.
• Freezing: High concentrations freeze at ~16°C (62°F).

Risks and safety

• Chemical Burns: Can cause severe skin burns and eye damage.
• Vapors: Inhaling vapors can damage lungs. Work in a ventilated area.
• Corrosion: Will destroy corks and some metals rapidly.

Related materials

• Vinegar: The raw material.
• Copper: Reacts to form Verdigris.
• Lead: Reacts to form Sugar of Lead.