Economic considerations
to be economically viable need to make as ammonia as possible as as possible and the conditions are a between these two factors.
Drugi mogući odgovor:
much
compromise
quickly
The reaction between nitrogen and hydrogen to form ammonia is reversible.
The reaction mixture can reach a dynamic equilibrium.
Which of these statements describes what is happening at equilibrium?
Put ticks (✓) in the boxes next to the two correct statements.
The reaction between nitrogen and hydrogen has stopped.
The forward and reverse reactions happen at the same time
The concentration of ammonia is increasing.
The forward and reverse reactions happen at the same rate.
The concentrations of nitrogen, hydrogen and ammonia are constant
All of the nitrogen and hydrogen react to make ammonia.
True
False
Economic considerations
to be economically viable need to make as ammonia as possible as as possible and the conditions are a between these two factors.
Temperature.
Higher temperature shifts equilibrium to as the reverse reaction is so the higher the temperature the the yield.
At lower temperature the rate of reaction is too
so a medium temperature of about 450°C is used
Pressure
higher pressure shifts equilibrium to the side with (LHS 4 gas moles vs RHS 2 gas moles).
The higher the pressure the the yield because forward reaction decreases
higher the pressure the tougher the reaction vessel has to be so that it does not burst
higher pressure increases .
medium pressure of atmospheres
Catalyst
catalyst gives more product in same
catalyst allows use of temperature for same rate
catalyst does not change position
(Note a catalyst provides an reaction pathway of lower energy so a greater proportion of the particles the activation energy so the frequency of collisions increases even though the total number of collisions is not changed).