Ammonia (NH3 (g), Delta. Hf = –54.9 kJ/mol ) reacts with oxygen to produce nitrogen and water (H2 O(g), Delta. Hf = –214.8 kJ/mol) according to the equation below. 4 upper N upper H subscript 3 (g) plus 3 upper O subscript 2 (g) right arrow 2 upper N subscript 2 (g) plus 6 upper H subscript 2 upper O (g).

What is the enthalpy of the reaction?
Use Delta H r x n equals the sum of delta H f of all the products minus the sum of delta H f of all the reactants.

One way in which the useful metal copper is produced is by dissolving the mineral azurite, which contains copper(ii) carbonate, in concentrated sulfuric acid. the sulfuric acid reacts with the copper(ii) carbonate to produce a blue solution of copper(ii) sulfate. scrap iron is then added to this solution, and pure copper metal precipitates out because of the following chemical reaction: (s) (aq) (s) (aq) suppose an industrial quality-control chemist analyzes a sample from a copper processing plant in the following way. he adds powdered iron to a copper(ii) sulfate sample from the plant until no more copper will precipitate. he then washes, dries, and weighs the precipitate, and finds that it has a mass of .