At 1000 K, Delta G deg per mole of O2 (kJ): CaO -1150; Al2O3 -1053; MnO -690; NiO -310; Ag2O +60. For 2C + O2 -> 2CO, Delta G deg = -221 - 0.179 T kJ. Which statements are correct at 1000 K?

Ag2O decomposes into silver and oxygen without any reductant

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3mt215

At 1000 K, $Δ G^{\circ}$ per mole of $O X_{2}$ (kJ): $CaO$ $- 1150$ ; $Al X_{2} O X_{3}$ $- 1053$ ; $MnO$ $- 690$ ; $NiO$ $- 310$ ; $Ag X_{2} O$ $+ 60$ . For $2 C + O X_{2} 2 CO$ , $Δ G^{\circ} = - 221 - 0.179 T$ kJ. Which statements are correct at 1000 K?

Carbon line at 1000 K is

- 400

kJ. Al (

- 1053

) is below Mn (

- 690

): yes. C (

- 400

) is below NiO (

- 310

): yes.

Ag X_{2} O

has positive

Δ G_{f}

, so decomposition is spontaneous. C (

- 400

) is above MnO (

- 690

): it cannot reduce it.