For CHEM 243 students

Conventions: 
The BestChoice module uses slightly different symbolism to indicate particular types of enthalpy or free energy changes than was used in your lectures in that the subscript is directly after the Δ as shown below. 

  lectures BestChoice
 enthalpy of formation  ΔHf ΔfH
 free energy of formation   ΔGf ΔfG
 enthalpy of reaction   ΔH ΔrH


Practice BestChoice problems:
If you wish to do a practice problem in BestChoice before doing the one in the assignment.  

For Thermodynamics, there are some that are comparable under the Enthalpy and Energy, Entropy and Free Energy sections of the main menu.  For Electrochemistry, see the corresponding section of the menu.

If you are looking for a particular type of problem, you can flick through the modules using the arrow keys near the header, or better still, complete the module.  Those modules take on average 20 minutes to complete.

A few words of advice:
We suggest that you do calculations on pen and paper before entering the answers into BestChoice.
Pay attention to the units associated with the numbers particularly in calculations involving Free Energy. 
Note that some of the numbers that you calculate will have negative signs!!

BestChoice marks are sent back to the server when you leave the page.  If you simply shut the browser window, it is possible that the last questions answered will not be submitted.  These will be available for you to complete on a subsequent session.