Pharmacopeial Inorganic Acids, Bases, and Buffers

H₃BO₃

Boric Acid

Characteristics of Boric Acid

• Weak acid (pKa = 9.19)

• mild antiseptic

• used for isotonicity adjustments

• used for buffer solutions

H₂SO₄

Sulfuric Acid

Characteristics of Sulfuric Acid

• dehydrating

• sulfonating/sulfating agent

• diprotic

H₃PO₄

Phosphoric acid

Concentration of diluted acids

9.5 - 10.5% w/v

Characteristics of Phosphoric acid

• used for buffer solutions

• salt formation of weak bases

• polyprotic

HCl

Hydrochloric Acid

Characteristics of Hydrochloric acid

• gastric acidifier

• salt formation on weak bases

• Technical grade: muriatic acid

HNO₃

Nitric Acid

Characteristics of Nitric Acid

• fumes, oxidizing

• Component of aqua regia

Aqua regia

• a solution that is able to dissolve gold

• made with 3 parts of concentrated HCl and 1 part HNO₃

NH₃

Strong Ammonia Solution

Characteristics of Strong Ammonia Solution

• Alkalinifier

• Central nervous system stimulant

• weak base

Na₂CO₃

Sodium Carbonate or Soda Ash

Characteristics of Sodium Carbonate

• Alkalinifier

• Sodium salt of weakly acidic drugs

• HCO₃^-: electrolyte and antacid

Ca(OH)₂

Calcium Hydroxide or “slaked lime”

Characteristics of Calcium Hydroxide

• easily absorbs CO₂ in the air

• soap production

• gas trap (with NaOH)

KOH

Potassium hydroxide

Characteristics of Potassium hydroxide

• deliquescent

• hygroscopic

• easily absorbs CO₂

• saponifying agent

• alkalinifier

NaOH

Sodium hydroxide or “Caustic Soda”

Characteristics of Sodium hydroxide

• deliquescent

• hygroscopic

• easily absorbs CO₂

• saponifying agent

• alkalinifier