Indicate how the concentration of each species in the chemical equation will change to reestablish equilibrium after a decrease in pressure or volume. If there is no change in the concentration of the species, leave the box blank. CH 4 ( g ) + 2 H 2 S ( g ) − ⇀ ↽ − CS 2 ( g ) + 4 H 2 ( g ) CH4(g)+2H2S(g)↽−−⇀CS2(g)+4H2(g) after decreasing the pressure after decreasing the volume of the reaction vessel