If you could explain how to solve this that’ll be great, thanks A chemical engin
ID: 1031820 • Letter: I
Question
If you could explain how to solve this that’ll be great, thanks A chemical engineer is studying the two reactions shown in the table below t a constant temperature of 21.0 °C and constant total pressure. Then, he measures the reaction enthalpy and reaction entropy AS of the first reaction, and the reaction enthalpy AH and reaction free energy G of the second reaction. The results of his measurements are shown in the table. Complete the table. That is, calculate G for the first reaction and S for the second. (Round your answer to zero decimal places.) Then decide whether under the conditions the engineer has set up, the reaction is spontaneous, the reverse reaction is spontaneous, or neither forward nor reverse reaction is spontaneous because the system is at equilibrium. // 1005 S 3352 Which is spontaneous? o this reaction the reverse reaction o neither 2Al(') + Fe,o,0) A,0,0) + 2Fe(s) Which is spontaneous? o this reaction the reverse reactien o neitherExplanation / Answer
Gibbs free energy is the energy associated with a chemical reaction that can do useful work. It equals the enthalpy minus the product of the temperature and entropy of the system.
G = H – TS
At constant temperature
G = H – TS
G predicts the direction of a chemical reaction. If G is negative, then the reaction is spontaneous. If G is positive, then the reaction is non-spontaneous.
(a) PF5 (g) + 10H2 (g) ----> P4(g) + 20HF , T = 21 °C = 294 K
G = 1005 - 294 x 3.352 = 19.512 kJ
Since G is positive implies this forward reaction is non spontaneous.
Thus the reverse reaction will be spontaneous since then G= -19.512 (negative)
(b) Fe2O3 + 2Al —> Al2O3 + 2Fe
S = (H - G) / T = -2.819 kJ K-1 = -2819 J K-1
Since G is negative implies this forward reaction is spontaneous.
When S is negative and H is negative, a process is spontaneous at low temperatures, where exothermicity is important.
Thank You