thermochemistry/ calrometry Flashcards
what is thermochemistry?
study of the role of heat in physical & chemical changes.
what is enthalpy?
- heat
- sum of kinetic & chemical energies for a system
what’s a system?
the thing your working with
what is temperature?
measure of a system’s kinetic energy
what is kinetic?
energy of motion
Q=mc deltaT
things to remember..?
q- quantity of kinetic energy (J)
m- mass in g
c- specific heat capacity (J/g°C)
delta- change/ difference in
t- temperature
mass n capacity must always be +
what is specific heat capacity?
how much energy it takes to heat something
what is endothermic?
use to determine system
-energy absorbed
-Q>0; TF>To
- increase in temp
what is exothermic?
use to determine system
-energy released
-Q<0;TF<To
-decrease in temp
what is chemical potential energy?
energy stores in chemical bonds
cannot be measured directly
deltaH=ndeltaHm
deltaH- enthalpy change (kJ)
n- # of moles (mol)
deltaHm- molar enthalpy of change (kj/mol)
what is fusion?
melting
(solid to liquid state)
endo
what is evaporation/vaporizing?
boiling
(liquid to gas state)
endo
what is sublimation?
dry ice-solid CO2
solid to gas state
endothermic
what is solidification?
freezing
(liquid to solid state)
exo
what is condensation?
rain
gas to liquid state
exo
what is deposition?
gas to solid state
exothermic
what’s a complex enthalpy change?
changes in energy involving kinetic & potential energy
(heating curve)
what’s deltaEk?
kinetic energy
what’s deltaEp?
potential energy
what is calorimetry?
chemical potential energy, cannot he measure directly
-Qexo=Qendo
(Qendo + Qexo=0)
Qendo + Qexo = 0
mcdeltaT + mcdeltaT = 0
