Ostwald Process NO Oxidation

4NH3 + 5O2 → 4NO + 6H2O

Overview

Ammonia is catalytically oxidized to nitric oxide over a platinum-rhodium gauze catalyst at about 850 C in the Ostwald process. Nitrogen is oxidized from -3 in NH₃ to +2 in NO. The NO is further oxidized to NO₂ and absorbed in water to make nitric acid. This process links the Haber process to nitric acid production.

Participants

Role Substance Coefficient State
Reactant Ammonia NH₃ 4 (g)
Reactant Oxygen O 5 (g)
Product Water H₂O 6 (g)

Everyday Example

Nearly all explosives, from TNT to ammonium nitrate, begin with nitric acid produced by this catalytic oxidation of ammonia.

Industrial Importance

The Ostwald process produces virtually all the world's nitric acid, essential for fertilizers (ammonium nitrate), explosives, and chemical manufacturing.

Properties

Type
Redox
Reversible
No
Energy
Exothermic
ΔH
-905.0 kJ/mol
Catalyst
Platinum-rhodium gauze

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Frequently Asked Questions

What is the equation for Ostwald Process NO Oxidation?
The balanced equation is: 4NH₃ + 5O₂ → 4NO + 6H₂O.
What type of reaction is Ostwald Process NO Oxidation?
Ostwald Process NO Oxidation is a redox reaction.
Is Ostwald Process NO Oxidation exothermic or endothermic?
Ostwald Process NO Oxidation is exothermic (releases energy). The enthalpy change (ΔH) is -905.0 kJ/mol.
What conditions are needed for Ostwald Process NO Oxidation?
This reaction requires a catalyst (Platinum-rhodium gauze).