Sodium Hydroxide and Iron(III) Chloride (Rust Color)

3NaOH + FeCl3 → Fe(OH)3 + 3NaCl

Overview

When sodium hydroxide is added to iron(III) chloride solution, a characteristic rust-brown precipitate of iron(III) hydroxide forms. This gelatinous precipitate is used to identify iron(III) ions in qualitative analysis.

Participants

Role Substance Coefficient State
Reactant Iron(III) Chloride FeCl₃ 1 (aq)
Reactant Sodium Hydroxide NaOH 3 (aq)
Product Sodium Chloride NaCl 3 (aq)

Everyday Example

The rust-colored sludge in water treatment plants is often iron(III) hydroxide formed by adding base to iron-containing water.

Industrial Importance

Iron(III) hydroxide is used as a pigment (iron oxide yellow after calcination), in water treatment as a coagulant, and in phosphate removal from wastewater.

Properties

Type
Double Replacement
Reversible
No
Energy
Exothermic
ΔH
-88.0 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 Iron(III) Chloride (Rust Color)?
The balanced equation is: 3NaOH + FeCl₃ → Fe(OH)₃ + 3NaCl.
What type of reaction is Sodium Hydroxide and Iron(III) Chloride (Rust Color)?
Sodium Hydroxide and Iron(III) Chloride (Rust Color) is a double replacement reaction.
Is Sodium Hydroxide and Iron(III) Chloride (Rust Color) exothermic or endothermic?
Sodium Hydroxide and Iron(III) Chloride (Rust Color) is exothermic (releases energy). The enthalpy change (ΔH) is -88.0 kJ/mol.