C

Catalyst

Ea reduced via alternative pathway; rate = k[A]^m[B]^n
Quick Reference
Formula / NotationEa reduced via alternative pathway; rate = k[A]^m[B]^n
Also Known AsChemical catalyst, Homogeneous catalyst, Heterogeneous catalyst, Biocatalyst

What is Catalyst?

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process, by providing an alternative reaction pathway with a lower activation energy. Catalysts are recovered unchanged at the end of the reaction. They can be homogeneous (same phase as reactants) or heterogeneous (different phase). Enzymes are biological catalysts.

Formula & Notation

Ea reduced via alternative pathway; rate = k[A]^m[B]^n

Other Names / Synonyms: Chemical catalyst, Homogeneous catalyst, Heterogeneous catalyst, Biocatalyst

Properties & Characteristics

Catalysts increase reaction rate by lowering activation energy Ea without being consumed or appearing in the overall equation. Homogeneous: same phase as reactants (e.g., H₂SO₄ catalyzing esterification). Heterogeneous: different phase (e.g., Fe in Haber process, Pt in catalytic converters, V₂O₅ in Contact process). Enzyme (biocatalyst): highly specific, operates at mild conditions, uses active site. Catalyst does NOT change equilibrium constant K — only rate of reaching equilibrium. Turnover number (TON) measures catalyst efficiency.

Uses & Applications

Industrial synthesis of ammonia (iron catalyst). Petroleum cracking and reforming (zeolite catalysts). Catalytic converters in vehicles (Pt, Pd, Rh — converts CO, NOx, hydrocarbons). Contact process for H₂SO₄ (V₂O₅). Polymerization catalysts (Ziegler-Natta for polyethylene). Enzyme catalysts in brewing, cheese making, baking, laundry detergents. Pharmaceutical synthesis. Environmental remediation.

Safety Information

Catalysts can dramatically accelerate reactions — ensure thermal management before introducing catalysts into exothermic systems. Pyrophoric catalysts (finely divided Pt, Raney nickel) ignite spontaneously in air — handle under inert atmosphere. Some industrial catalysts are toxic (chromium oxide, nickel carbonyl). Enzymes: avoid skin contact (protease enzymes in detergents can cause allergic reactions).

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Catalyst
Formula Ea reduced via alternative pathway; rate = k[A]^m[B]^n
Synonyms Chemical catalyst, Homogeneous catalyst, Heterogeneous catalyst, Biocatalyst

Frequently Asked Questions

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process, by providing an alternative reaction pathway with a lower activation energy. Catalysts are recovered unchanged at the end of the reaction. They can be homogeneous (same phase as reactants) or heterogeneous (different phase). Enzymes are biological catalysts.

More "C" Terms

View all "C" terms →
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z