<P> Nitrogen (N) is very unreactive because the molecules are held together by strong triple bonds . The Haber process relies on catalysts that accelerate the scission of this triple bond . </P> <P> Two opposing considerations are relevant to this synthesis: the position of the equilibrium and the rate of reaction . At room temperature, the equilibrium is strongly in favor of ammonia, but the reaction doesn't proceed at a detectable rate . The obvious solution is to raise the temperature, but because the reaction is exothermic, the equilibrium constant (using bar or atm units) becomes 1 around 150--200 ° C (302--392 ° F). (See Le Châtelier's principle .) </P> <Table> K (T) for N + 3 H ⇌ 2 NH <Tr> <Th> Temperature (° C) </Th> <Th> </Th> </Tr> <Tr> <Td> 300 </Td> <Td> 4.34 × 10 </Td> </Tr> <Tr> <Td> 400 </Td> <Td> 1.64 × 10 </Td> </Tr> <Tr> <Td> 450 </Td> <Td> 4.51 × 10 </Td> </Tr> <Tr> <Td> 500 </Td> <Td> 1.45 × 10 </Td> </Tr> <Tr> <Td> 550 </Td> <Td> 5.38 × 10 </Td> </Tr> <Tr> <Td> 600 </Td> <Td> 2.25 × 10 </Td> </Tr> </Table> <Tr> <Th> Temperature (° C) </Th> <Th> </Th> </Tr>

How ammonia is prepared by haber's process