Ethene \(\left(\mathrm{C}_{2} \mathrm{H}_{4}\right)\) can be halogenated by the reaction:
\(\mathrm{C}_{2} \mathrm{H}_{4}(g)+\mathrm{X}_{2}(g) \rightleftharpoons \mathrm{C}_{2} \mathrm{H}_{4} \mathrm{X}_{2}(g)\)
where \(\mathrm{X}_{2}\) can be \(\mathrm{Cl}_{2}, \mathrm{Br}_{2}\), or \(\mathrm{I}_{2}\). Use the thermodynamic data given to calculate \(\Delta H^{\circ}, \Delta S^{\circ}, \Delta G^{\circ}\), and \(K_{\mathrm{p}}\) for the halogenation reaction by each of the three halogens at \(25^{\circ} \mathrm{C}\). Which reaction is most spontaneous? Least spontaneous? What is the main factor responsible for the difference in the spontaneity of the three reactions? Does higher temperature make the reactions more spontaneous or less spontaneous?
Text Transcription:
(C2H4)
C2H4( g) + X2( g) rightleftharpoons C2H4X2( g)
X_2
Cl_2, Br_2
I_2
Delta H^circ
Delta S^circ
Delta G^circ
K_p
25^circ C
Name:__Rachel Jefferies__________________ 1.Stateandexplainthelawofconservationofmass The law of conservation of mass states that in a chemical reaction, matter is neither created or destroyed. So when combining two elements such as sodium and chloride, the mass of the compound is equal to the mass of both individual elements added together. This proves that no atoms were destroyed in the process. 2.Stateandexplainthelawofdefiniteproportions The law of definite proportions (or the law of constant composition) states that “All samples of a given compound, regardless of their source of how they were prepared, have the same proportions of their constituent elements”. Ex. Decomposition of 18 g of water = 16 g of oxygen and 2 g of hydrogen. Oxygen-Hydrogen Mass ratio = 16 g O/ 2 g H = 8.0 3.Stateandexplainthelawofmultipleproportions.Howisthelawofmultipleproportions different fromthelawofdefiniteproportions The law of multiple proportions states that, “When two elements form (call them A and B) two different compounds, the masses of element B that combines with 1 gram of element A can be expressed as a ratio of small whole numbers”. Ex. The mass ratio of oxygen to carbon in carbon dioxide is 2.67:1. Therefore, 2.67 g of oxygen reacts with 1 gram of carbon. In carbon monoxide, however, the mass ratio of oxygen to carbon is 1.33:1, or 1.33 g of oxygen to every 1 g of carbon. Mass oxygen to 1 g of carbon in carbon dioxide2.67 Mass oxygen to 1 g of carbon in carbon monox