The diagram shows a gas syringe with a free-moving piston. The syringe contains gaseous hydrogen, gaseous iodine and gaseous hydrogen iodide at equilibrium. [Figure of gas syringe] H2(g) + I2(g) ⇌ 2HI(g) Three changes are listed. 1 increasing the total pressure by adding an inert gas and keeping the volume constant 2 increasing the pressure by adding more gaseous hydrogen iodide and keeping the volume constant 3 decreasing the volume by pushing the piston to the left Which changes will result in an equilibrium position at which the rate of the forward reaction has increased?

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