Question

Catalytic converters are fitted into automobiles to reduce emission of harmful gases. Catalytic converters change unburnt hydrocarbons into:

• A. methane
  
• B. carbon dioxide and water
  
• C. carbon monoxide
  
• D. carbon dioxide and methane

Answer 1

The correct option is B carbon dioxide and water


Catalytic converter

A catalytic converter uses a catalyst to change the harmful compounds emitted by an automobile engine into relatively less toxic gases like carbon dioxide and steam.



Mechanism of action

• Platinum-palladium and rhodium catalysts present in the converters help in oxidising and converting toxic by-products (formed due to unburnt hydrocarbons) into non-hazardous substances.
• For example:-
  • Hydrocarbons are converted to carbon dioxide and water
  • Carbon monoxide is converted to carbon dioxide
  • Nitric oxide is converted to nitrogen gas

Mechanism of action:

$CO+O_2\to C{O}_2$

$C_x{H}_{4x}+2x{O}_2\to xC{O}_2+2x{H}_{2}O$
(Hydrocarbon)

Final answer
a. carbon dioxide and water