For the reaction CO(g)+(1/2)O2(g) xrightarrow[] CO2(g),Δ H and Δ S are -283kJ and -87JK-1, respectively. It was intended to carry out this reaction at 1000 , 1500 , 3000 and 3500 K. At which of these temperatures would this reaction be thermodynamically spontaneous?

Question

For the reaction CO(g)+(1/2)O2(g) xrightarrow[] CO2(g),Δ H and Δ S are -283kJ and -87JK-1, respectively. It was intended to carry out this reaction at 1000 , 1500 , 3000 and 3500 K. At which of these temperatures would this reaction be thermodynamically spontaneous? (A) 1500 and 3500 K (B) 3000 and 3500 K (C) 1000, 1500 and 3000 K (D) 1500, 3000 and 3500 K

Tardigrade Admin · Accepted Answer

∵ Δ G=Δ H-T.Δ S For a spontaneous reaction Δ G should be negative Δ H=-238 text kJ,Δ S=- text 87 text JK-1 Hence, reaction will be spontaneous when Δ H>T.Δ S . Therefore, at 1000, 1500 and 3000 K the reaction would be spontaneous.

1500 and 3500 K

3000 and 3500 K

1000, 1500 and 3000 K

1500, 3000 and 3500 K

At all these temperatures

$∵$ $Δ G = Δ H - T .Δ S$ For a spontaneous reaction $Δ G$ should be negative $Δ H = - 238 k J, Δ S = - 87 J K^{- 1}$ Hence, reaction will be spontaneous when $Δ H > T .Δ S$ . Therefore, at 1000, 1500 and 3000 K the reaction would be spontaneous.

Q. For the reaction CO(g)+21​O2​(g)​ CO2​(g),ΔH and ΔS are −283kJ and −87JK−1, respectively. It was intended to carry out this reaction at 1000 , 1500 , 3000 and 3500 K. At which of these temperatures would this reaction be thermodynamically spontaneous?