Calculating deltaH°f for O(g) - 142.0 kJ/mol

Thread starter NickP717
Start date Dec 3, 2008

AI Thread Summary

To calculate the standard enthalpy of formation (deltaH°f) for atomic oxygen (O(g)), one should consider the bond energy of O2(g), which is 142.0 kJ/mol. Since the formation of one mole of O(g) from O2(g) involves breaking the O=O bond, the deltaH°f for O(g) can be determined by halving the bond energy of O2. This approach is based on the principle that breaking a bond requires energy input, thus reflecting the enthalpy change. The calculation yields a deltaH°f of 71.0 kJ/mol for O(g). This method effectively addresses the problem of finding the enthalpy for the formation of a single oxygen atom.

Dec 3, 2008

NickP717

Homework Statement

The bond energy of O2(g) is 142.0 kJ/mol. Calculate deltaH°f for O(g).

Homework Equations

The Attempt at a Solution

no clue

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Dec 3, 2008

lucky_star

Hi Nick,
You have an Oxygen molecule and it asks you for the delta Hf of Oxygen atom ONLY. So, i would suggest you to halve the bond energy of O2.

Any other suggestions or am I right?

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