Page 1 of 1

Gibbs v internal

Posted: Wed Jan 25, 2017 3:47 pm
by 704709603
Hi,
What is the difference bw delta G and delta U? When calculating using the standard free energy of formation (the 3rd method) why is it specified that it is the "of formation" i.e. does it mean the free energy change when a molecule is formed (bonds made)?
Thank you!

Re: Gibbs v internal

Posted: Wed Jan 25, 2017 11:55 pm
by Katherine_Zhuo_3B
U stands for internal energy, and delta U stands for the change in internal energy, which can be calculated by delta U = q + w. G is for Gibbs Free Energy, and delta G stands for the change in free energy of a system, which can help determine the spontaneity and favorability of a reaction. There are several ways to calculate delta G, and one way is by utilizing the standard free energies of formation. The standard free energy of formation is the change in free energy of substance and its elements in its most stable states under standard state conditions (1 atm and 298 K).