Catalytic converter
Ir 1%, Pd 1%, Pt 1%, Rh 1%,

estimated elemental composition and empirical formula weight 
Real, long lived, electronically neutral reagent chemical.

Gram formula weight (molecular mass) = 596.62
Solubility in organics = insoluble

Commercial product.Catalytic converters are placed close to the engine so that they run hot.
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Catalytic converter
is defined with respect to the entities below:
The entities below are defined with respect to:
Catalytic converter
Catalyst (AS/A2 generic)

Transition metal, first row (AS/A2 generic)

chemical compound molecule metal molecular science reaction mechanism ionic material acid base geometry reactivity synthesis science knowledge chemistry Lewis