Calorimetry (AKA Heat Problems or Thermochemistry) Flashcards
Heat being absorbed is an example of an_______ process.
endothermic
Heat being released is an example of an ________ process
exothermic
H2O (l) –> H2O (s) is an _______ process and the word Heat would be put on the _______ side of the arrow.
exothermic; right
What is sublimation? Give 2 examples of substances that undergo it.
Solid changing to gas without turning into a liquid first. ; dry ice (CO2) or Iodine (s)
What is fusion and what equation do you use for it?
melting; q= mHf
Why is there no temperature change when a solid becomes a liquid at the melting point?
The heat energy is being absorbed in order to change phase and increase the PE. The temperature won’t go up until all the molecules have changed phase.
What is the technical definition of temperature in terms of molecular movement?
Temperature is defined as the average kinetic energy of molecules.
On a phase change diagram, when does KE go up?
During a slant of the line (when the temperature is changing)
What phase of matter has the most PE?
Gas has the most PE.
What does entropy refer to? What phase of matter has the most entropy?
Randomness or disorder of a system (or substance); Gases have the most entropy.
When would you use the equation: q= mcDeltaT?
When you want to know how much heat is absorbed or released by a substance that undergoes a change in temperature..
What is the unit for specific heat capacity?
J/gC
What is the opposite of vaporization? What phase change occurs?
Condensation; Gas –> liquid
At what temperature does vaporization occur?
The boiling point.
What is the difference between evaporation and vaporization?
evaporation can occur at room temperature; vaporization occurs at the boiling point.
