Without a catalyst the efficiency of ammonia synthesis is very low, no matter how we vary the pressure and temperature. 

    But the presence of a catalyst makes things entirely different. Ordinary metallic iron with an admixture of aluminium and potassium oxides accelerates the reaction considerably.

    Twentieth-century chemistry owes its unprecedented progress to the use of catalysts. Nor is this all. 

    Various vital processes occur in animal and plant organisms owing to the presence of special catalysts called enzymes.

    The chemistry of all animate and inanimate nature, such is the range of these wonderful accelerators!

    But what if we take a copper, aluminium or iron wire instead of a platinum one? Will the vessel walls again become foggy? 

    Alas! Hydrogen and oxygen display no inclination to react as they did when urged on by the magic platinum wand...
 

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