1. Kinetics Entropy Lesson
Crash Course Chemistry – Entropy 2:35-

2. Thermodynamics - the study of the relationship of heat and other energy forms that accompany all physical and chemical changes in matter.
(Provides no information about the rate or speed of reactions)

3. Spontaneous Processes - proceeds on its own without any outside intervention.
Examples:
ice melting at rm temp cooling of a hot object
water flowing down hill soda fizzing when opened
radioactive decay iron rusting

4. Spontaneous processes are driven by a tendency to reach a state of minimum potential energy because low potential energy represents a stable situation.
Most spontaneous processes are exothermic

5. ΔH = Hproducts - Hreactants
Enthalpy - refers to the transfer of energy
ΔH = Hproducts - Hreactants

6. Endothermic Reaction (+ΔH)
Hreactants < Hproducts
PEreactants < PEproducts

7. Exothermic Reaction (-ΔH)
Hreactants > Hproducts
PEreactants > PEproducts

8. Are the reverse reactions of the examples above also spontaneous?
No, the reverse process generally require an expenditure of more energy.

9. - a quantitative measure of the disorder,
 Entropy (S)
- a quantitative measure of the disorder,
or randomness in the substances in a reaction.   
Solid Liquid Gas

10. Entropy when gases are formed from liquids and solids.
CO2(s) → CO2(g)
H2O(l) → H2O(g)
increases

11. Entropy (S) 2nd Law of Thermodynamics – Entropy – Words/Letters
Chemistry An Atoms Focused Approach Chap 12 - Entropy

12. Entropy when solutions are formed from liquids and solids.
NaCl(s) → Na+(aq) + Cl-(aq)
increases
H2O

13. Entropy when there are more molecules
of gas as products than there are as reactants.
2NH3(g) → N2(g) + 3H2(g)
NH4Cl(s) → NH3(g) + HCl(g)
increases

14. Entropy when the temperature of a substance is increased.
H2O(l, 25◦C) → H2O(l, 50 ◦C)
increases

15. Thermodynamic Law
- states that in any spontaneous process, the overall entropy of the universe always
There is a strong tendency for things to become
increases.
more disordered.

16. The entropy of the surroundings increases or decreases because of the heat transfer by a reaction
An exothermic reaction (-ΔH) heats up the surroundings, increasing the entropy of the surroundings
An endothermic reaction (+ΔH) cools the surroundings, decreasing the entropy of the surroundings

17. Entropy (S) The Mixing of Ideal Gases  
The Mixing of Ideal Gases
For our example, we shall again consider a simple system of two ideal gases, A and B, with a number of moles nA and nB, at a certain constant temperature and pressure in volumes of VA and VB, as shown in Figure 1. These two gases are separated by a partition so they are each sequestered in their respective volumes. If we now remove the partition (like opening a window in the example above), we expect the two gases to randomly diffuse and form a homogenous mixture as we see in Figure 2.