Standard Enthalpies of Formation 8'9

1
Standard Enthalpies of Formation 8.9
Slide 1

• Hesss Law is much more useful if you know lots
  of reactions.
• DHº table is made of standard heats of
  formation. The amount of heat needed to for 1
  mole of a compound from its elements in their
  standard states.
• Standard states are 1 atm, 1M and 25ºC
• For an element it is 0
• There is a table on pg 317 and in appendix pg
  A-11 through A15

2
Since we can manipulate the equations
Slide 2

• We can use heats of formation to figure out the
  heat of reaction.
• Lets do it with this equation.
• C2H5OH 3O2(g) 2CO2 3H2O
• which leads us to this rule.