Consider the equilibrium system below. Upper N upper H subscript 4 upper H upper S (s) double-headed arrow upper N upper H subscript 4 upper C l (g). If the system is at dynamic equilibrium, which statement is true? Sublimation of the NH4CI crystals stops. Solidification of the NH4CI vapors stops. The rate of sublimation of the NH4CI crystals is equal to the rate of solidification of the NH4CI vapors. The rate of sublimation of the NH4CI crystals is higher than the rate of solidification of the NH4CI vapors.

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. in the first step, calcium carbide and water react to form acetylene and calcium hydroxide: cac2 (s) + 2h2o (g) → c2h2 (g) + caoh2 (s) =δh−414.kj in the second step, acetylene, carbon dioxide and water react to form acrylic acid: 6c2h2 (g) + 3co2 (g) + 4h2o (g) → 5ch2chco2h (g) =δh132.kj calculate the net change in enthalpy for the formation of one mole of acrylic acid from calcium carbide, water and carbon dioxide from these reactions. round your answer to the nearest kj .