Increasing the pressure has NO effect on the position of the equilibrium H2 + I2 gives 2HI because
- A. the reaction is exothermic
- B. hydrogen iodide is a gas
- C. the number of moles of gas is the same on both sides
- D. the reaction has no catalyst
Explanation
Pressure changes shift an equilibrium only when the two sides differ in the number of gas molecules, and here there are two moles on each side, so neither direction relieves the stress. The rate of reaching equilibrium does rise with pressure, but the position stays put. Temperature changes will still shift this equilibrium, since the two directions differ in enthalpy.
Related questions
For the equilibrium N2 + 3H2 gives 2NH3, which is exothermic, the yield of ammonia is increased by
Adding a catalyst to a system at equilibrium
For an endothermic reaction at equilibrium, raising the temperature will
In the reaction A + B gives C + D at equilibrium, adding more of substance A will
Le Chatelier's principle states that when a stress is applied to a system at equilibrium, the system