Entropy - Thermodynamics Pt B (3.5)

Question 1

What is enthalpy change?

Answer 1

• amount of energy lost/gained by a system ( not telling us whether a reaction will happen or not)

Question 2

What is a spontaneous reaction?

Answer 2

• occurs without the addition of any energy (exothermic/ endothermic)

Question 3

What is entropy?

Answer 3

Measure of disorder in a system

Question 4

Spontaneous reactions usually don’t involve an increase in entropy or disorder of the system. True or False?

Answer 4

False - spontaneous requires energy

Question 5

What does the second law of thermodynamics stae?

Answer 5

• entropy of the universe increases in a spontaneous process

Question 6

A problem to note:

Answer 6

• water forms ice spontaneously when it cools
• but liquids have more entropy thsn solids
• that is why spontaneous reactions also depend on entropy change of the surroundings
• energy can be released/absorbed

Question 7

If Gibbs Energy is negative, the reaction is?

Answer 7

Spontaneous