{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Chapter 19 - chemical thermodynamics - outline 5-7-00

Temperature of the system at 298 k(25 o c = standard

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: temperature of the system at 298 K ** (25 O C = standard temp. for equilibria) Chemical Thermodynamics ∆ G represents the part of that total energy which can be harnessed to do useful work during the transfer, i.e., the energy "free" to do work From this we might say: ∆ H = ∆ G + "unfree" energy By now you might suspect--and correctly--that the "unfree" energy term involves what we have called the entropy change, ∆ S . We know that the entropy change of the system is connected to the entropy change of the surroundings which is highly temperature dependent. Thus the relationship above is generally written as: ∆ G o = ∆ H o - T ∆ S o This is known as the Gibbs-Helmholtz equation and is the absolute bottom line in chemical thermodynamics. Sort of. Remember in our definition of enthalpy (H) we said it was a "state function". The net enthalpy change ( ∆ H--which is the only kind of enthalpy quantity we can measure) is independent of path . Effect of Temperature on Reaction Spontaneity ∆ G o ∆ H o ∆ S o Reaction Characteristics example (opposite is true for reverse reaction) always negative - + spontaneous at all temp...
View Full Document

{[ snackBarMessage ]}

Page1 / 3

temperature of the system at 298 K(25 O C = standard temp...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon bookmark
Ask a homework question - tutors are online