The decomposition of calcium carbonate to calcium oxide and carbon dioxide only takes place at very high temperatures, making the direct measurement of h for this reaction difficult. both calcium carbonate and calcium oxide react readily with dilute hydrochloric acid at room temperature

So calculate the H for the other two reactions a room temperature and combine the reactions to calculate the H of the decomposition of calcium carbonate using the Hess's Law

Answerit curves up and levels out.explanationwe assume that the container contains absolutely no ammonia to begin with as it states that "nitrogen gas and hydrogen gas" react to "produce ammonia."at dynamic equilibrium, the product and reactant concentrations are equal.this means that, starting from a concentration of zero, [nh₃] must curve "up" from zero and then level out to a constant concentration.