Chapter 7.2

Question 1

What are state functions in comparison to process functions

Answer 1

State functions

• > describe the system in an equilibrium state
• > cannot describe how the system got to equilibrium

Process functions
->describe how the system got to an equilibrium state

Question 2

Give examples of state functions

Answer 2

State
->pressure, density, temperature, volume, enthalpy, internal energy, gibbs free energy and entropy

Process
->work and heat

Question 3

What are standard conditions

Answer 3

-they are defined as 25 degrees celcius, 1 atm pressure and 1 M concentrations

Question 4

What are standard temperature and pressure conditions

Answer 4

-temperature is defined as 0 degrees(273K) and pressure is 1 atm

Question 5

What are standard conditions used for

Answer 5

-they are used for kinetics, equilibrium, and thermodynamics

Question 6

What is STP used for

Answer 6

-it is used for ideal gas calculations

Question 7

Is evaporation an endothermic process

Answer 7

• yes it is

- >note each time the liquid loses a high-energy particle, the temperature of the remaining liquid decreases

Question 8

What is the difference between boiling and evaporation

Answer 8

Boiling

• > specific type of vaporization
• > occur only under certain conditions
• > it is the rapid bubbling of the entire liquid with rapid release of the liquid as gas particles

Evaporation
->evaporation happens in all liquids at all temperatures

Question 9

What is the vapor pressure of the liquid. How is it affected by temperature

Answer 9

• pressure that the gas exerts over the liquid at equilibrium
• it increases as temperature increases
• > because more molecules have a chance to escape into the gas phase from the liquid phase

Question 10

What is meant by the term sublimation? What is the opposite of sublimation?

Answer 10

• when a solid goes directly into the gas phase
• the opposite of sublimation is deposition
• > when a gas goes directly to a solid

Question 11

What is meant by the process of condensation

Answer 11

• the change in phase from gas to liquid

- happens with increased pressure and or decreased temperature

Question 12

How does boiling point relate to the vapor pressure

Answer 12

-boiling point is the temperature at which the vapor pressure of the liquid equals the ambient pressure(external, applied, incident)

Question 13

What is meant by the term fusion or melting

Answer 13

• transition from solid to liquid is called fusion or melting
• > the reverse from liquid to solid is called solidification, crystallization and or freezing

Question 14

What is the critical point

Answer 14

-temperature and pressure above which there is no distinction between the phases

• as a liquid is heated, its density decreases and the density of the vapor sitting above the liquid increases
• > at the critical point, the two densities become equal and there is no distinction between the two phases

-the heat of vaporization at this point and for all temperatures and pressures above the critical point values is zero