The synthesis of ammonia NH3 is an exothermic reaction that occurs through the Haber process, which involves the reaction between nitrogen gas N2 and hydrogen gas H2 under high pressure and temperature in the presence of an iron catalyst. The balanced equation for this reaction is:N2 g + 3H2 g 2NH3 g According to Le Chatelier's principle, if a system at equilibrium is subjected to a change in pressure, temperature, or concentration of reactants or products, the system will adjust its equilibrium position to counteract the change.In the case of the synthesis of ammonia, an increase in pressure will affect the equilibrium position and reaction direction as follows:1. The reaction involves a decrease in the number of moles of gas: On the left side of the equation, there are 4 moles of gas 1 mole of N2 and 3 moles of H2 , while on the right side, there are only 2 moles of NH3. When the pressure is increased, the system will try to counteract this change by shifting the equilibrium position to the side with fewer moles of gas, which is the side of the products NH3 .2. The reaction direction will shift towards the formation of ammonia: As the equilibrium position shifts to the right, the reaction will proceed in the forward direction, favoring the formation of ammonia. This means that more nitrogen and hydrogen will react to form ammonia, and the concentration of ammonia will increase.In summary, an increase in pressure will shift the equilibrium position of the synthesis of ammonia reaction towards the right, favoring the formation of ammonia, and the reaction direction will proceed in the forward direction. This is one of the reasons why the Haber process is carried out at high pressures, as it increases the yield of ammonia.