CHEM 151 Final Exam ACTUAL UPDATED QUESTIONS AND CORRECT ANSWERS
What are good differentiating characteristics? 1) having values that do not depend on the amount of substance (intensive
properties)
2) are unique for each substance
3) ex: boiling point, density, solubility
Gas ---> solid deposition
Solid ---> gas sublimation
Solid ---> liquid melting
Liquid ---> solid freezing
Liquid ---> gas vaporization
Gas ---> liquid condensation
, During a physical/phase change, what stays constant? temperature (represented horizontally)
During a phase change, what changes? the physical properties of the substance change
Temperature increases as a function of what? time
Temperature is a measure of what? the average kinetic energy (KE)
Gases have no interactions, what does this say about the there is none, all the same as gases
potential energy (PE)?
Lowest potential energy (PE) = ? strongest interactions
On the vapor pressure curves, the line with the highest VP the weakest interactions, the lowest boiling temperature, the highest potential
also has.. ? energy, and is the most volatile
Velocity depends on what? mass (aka the lightest will be the fastest)
What type of energy is talked about when we use a ΔE vs kinetic energy (vertical)
T plot (PE or KE)?
What type of energy is talked about when we talk about potential energy (horizontal)
phase change diagrams (PE or KE)?
What is a molecule? 2 or more atoms
What is a compound? 2 or more different atoms
What is vapor pressure (VP)? the pressure exerted by the vaporized substance
Boiling of a liquid occurs when what? when its vapor pressure equals the atmospheric pressure
What are good differentiating characteristics? 1) having values that do not depend on the amount of substance (intensive
properties)
2) are unique for each substance
3) ex: boiling point, density, solubility
Gas ---> solid deposition
Solid ---> gas sublimation
Solid ---> liquid melting
Liquid ---> solid freezing
Liquid ---> gas vaporization
Gas ---> liquid condensation
, During a physical/phase change, what stays constant? temperature (represented horizontally)
During a phase change, what changes? the physical properties of the substance change
Temperature increases as a function of what? time
Temperature is a measure of what? the average kinetic energy (KE)
Gases have no interactions, what does this say about the there is none, all the same as gases
potential energy (PE)?
Lowest potential energy (PE) = ? strongest interactions
On the vapor pressure curves, the line with the highest VP the weakest interactions, the lowest boiling temperature, the highest potential
also has.. ? energy, and is the most volatile
Velocity depends on what? mass (aka the lightest will be the fastest)
What type of energy is talked about when we use a ΔE vs kinetic energy (vertical)
T plot (PE or KE)?
What type of energy is talked about when we talk about potential energy (horizontal)
phase change diagrams (PE or KE)?
What is a molecule? 2 or more atoms
What is a compound? 2 or more different atoms
What is vapor pressure (VP)? the pressure exerted by the vaporized substance
Boiling of a liquid occurs when what? when its vapor pressure equals the atmospheric pressure
