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Use the average bond energies listed below to estimate how much more energy is released by the reaction C(s) +0₂(g) › CO₂(g) than by the reaction: C(s) + (1/2)O₂ (g) › CO (g)

User Nuno Sousa
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Final answer:

The formation of CO₂ releases 172.5 kJ more energy than the formation of CO for one mole of C(s) reacted, calculated by comparing ΔH values of -393.5 kJ for CO₂ and -221.0 kJ for 2 CO.

Step-by-step explanation:

To estimate how much more energy is released by the reaction C(s) + O₂(g) → CO₂(g) compared to C(s) + (1/2)O₂(g) → CO(g), we need to look at the energy changes involved in forming CO₂ and CO. The energy change for the formation of CO₂ from C(s) and O₂(g) is given as -393.5 kJ, while the bond enthalpies allow us to calculate the energy released in forming CO as 2 mol (-192.0 kJ mol⁻¹) + 2 mol (-85.5 kJ mol⁻¹) = -555 kJ. By subtracting the energy released in the CO formation from the CO₂ formation, we get the difference in released energy.

For the CO reaction:
2 CO(g) → 2 C(s) + O₂(g) ΔH = +221.0 kJ
By reversing this we get:
2 C(s) + O₂(g) → 2 CO(g) with ΔH = -221.0 kJ.

To determine the extra energy released by forming CO₂ versus CO, compare the two ΔH values:
-393.5 kJ (for CO₂) and -221.0 kJ (for 2 CO).
The difference is -393.5 kJ + 221.0 kJ = -172.5 kJ. Thus, the formation of CO₂ releases 172.5 kJ more energy than the formation of CO for one mole of C(s) reacted.

User Tomarto
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