For the reaction
`CO (g) + (1)/(2) O_(2) (g) rarr CO_(2) (g)`
`Delta H` and `Delta S` are `-283 kJ` and `-87 J K^(-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?

Options

A. 1500 and 3500 K
B. 3000 and 3500 K
C. 1000, 1500 and 3000K
D. 1500, 3000 and 3500 K

Answer

C

Explanation

`DeltaG=DeltaH-TDeltaS`
At 1000 K, `DeltaG=-283-(-1000xx0.087)`(Spontaneous)
`=-196kJ`
AT 1500K `DeltaG=-283-(-1500xx0.087)` (spontaneous)
`=-152.5kJ`
At 3000 K, `DeltaG=-283-(-3000xx0.087)` (spontaneous)
`=-22kJ`
At 3500 K, `DeltaG=-283-(-3500xx0.087)` (Non-spontaneous)
=`+21.5kJ`