Understanding Sodium Phosphate

Sodium Phosphate, known as Phospho Soda, with the chemical formula Na₃PO₄, is a saline laxative often used as a cleansing agent for procedures like a double contrast barium enema.

This compound is synthesized by neutralizing phosphoric acid with sodium hydroxide or sodium carbonate under controlled conditions. While sodium phosphate is the most common, potassium phosphate buffer and combinations of sodium and potassium are also frequently used. Sodium phosphate buffers are often used in the formulation of various pharmaceutical compounds.

Alternative names – Trisodium phosphate, Sodium orthophosphate, Tribasic sodium phosphate

The Structure of Sodium Phosphate – Na₃PO₄

Physical Characteristics of Sodium Phosphate – Na₃PO₄

Chemical Reactions Involving Sodium Phosphate – Na₃PO₄

• Sodium phosphate reacts with hydrochloric acid to form phosphoric acid and sodium chloride. The chemical equation for this reaction is as follows:
  Na₃PO₄ + 3HCl → H₃PO₄ + 3NaCl
• When sodium phosphate reacts with calcium chloride, it results in the formation of calcium phosphate and sodium chloride. The chemical equation for this reaction is:
  2Na₃PO₄ + 3CaCl₂ → 6NaCl + Ca₃(PO₄)₂

Applications of Sodium Phosphate – Na₃PO₄

• Local, short-term treatment of inflammation, with neomycin as a bacterial prophylaxis.
• Used post-glaucoma surgery or cataract surgery.
• Acts as a mild laxative and stimulates gall bladder emptying.
• Considered one of the most palatable saline laxatives. Also used as an oral solution for antihypercalcemia.
• Controls the pH of water and acts as a hardness precipitation and control agent in mildly acidic solutions.