Sodium Hydroxide and Phosphoric Acid
3NaOH + H3PO4 → Na3PO4 + 3H2O
Overview
Sodium hydroxide reacts with phosphoric acid in a 3:1 ratio to completely neutralize the triprotic acid, forming trisodium phosphate and water. Partial neutralization gives mono- or disodium phosphate depending on the molar ratio. Each salt has different industrial applications.
Participants
| Role | Substance | Coefficient | State |
|---|---|---|---|
| Reactant | Phosphoric Acid H₃PO₄ | 1 | (aq) |
| Reactant | Sodium Hydroxide NaOH | 3 | (aq) |
| Product | Water H₂O | 3 | (l) |
Everyday Example
Trisodium phosphate (TSP) was once the main ingredient in heavy-duty household cleaners and dishwasher detergents before environmental regulations limited phosphate use.
Industrial Importance
Sodium phosphates are used in food processing, water treatment, cleaning products, and as buffering agents. Environmental phosphate regulations have changed their industrial use patterns.
Properties
- Type
- Double Replacement
- Reversible
- No
- Energy
- Exothermic
- ΔH
- -173.0 kJ/mol
Related Reactions
Aluminum Hydroxide and Hydrochloric Acid
Ammonia and Hydrochloric Acid (White Smoke)
Barium Chloride and Sodium Sulfate Precipitation
Calcium Carbonate and Hydrochloric Acid
Calcium Chloride and Sodium Carbonate
Calcium Hydroxide and Carbon Dioxide (Limewater Test)
Calcium Hydroxide and Sulfuric Acid
Copper(II) Sulfate and Sodium Hydroxide
Iron(III) Chloride and Sodium Hydroxide
Lead Nitrate and Potassium Iodide (Golden Rain)
Frequently Asked Questions
What is the equation for Sodium Hydroxide and Phosphoric Acid?
The balanced equation is: 3NaOH + H₃PO₄ → Na₃PO₄ + 3H₂O.
What type of reaction is Sodium Hydroxide and Phosphoric Acid?
Sodium Hydroxide and Phosphoric Acid is a double replacement reaction.
Is Sodium Hydroxide and Phosphoric Acid exothermic or endothermic?
Sodium Hydroxide and Phosphoric Acid is exothermic (releases energy). The enthalpy change (ΔH) is -173.0 kJ/mol.