Thermochemistry Formulas Flashcards
Formula for Work
W = F * d
W = - (P∆T)
F = force
d = distance
Formula for Potential Energy
PE= m * g * h
m = mass
g = force of gravity
h = height
Formula for Kinetic energy
KE = (1/2) mu^2
m = mass
u = speed
Formula for change in Energy (∆E)
∆E= q + w
q = OTHER energy gained
w = work
Formula for the First Law of thermodynamics
∆E System + ∆E Surroundings = 0
What sign is heat if Heat going IN the system ?
q > 0
( Positive )
What sign is Heat if Heat is going OUT of the system ?
q < 0
( Negative )
What sign is work if Work is done ON the system?
w > 0
( Positive integer )
What sign is work if work is done BY the system?
w < 0
( Negative )
Endothermic
What happens to Energy?
What is its sign?
Energy is ABSORBED meaning Energy INCREASES
It has a POSITIVE sign
Exothermic
What happens to Energy?
What is its sign?
Energy is RELEASED meaning Energy DECREASES
Its sign is NEGATIVE
What is the sign of ∆E & Is it Endo/Exo?
q →goes into the system
W→goes out of sys. and into surr.
Sign:
+ , - , 0
Process:
ENDOTHERMIC
What is the sign of ∆E & Is it Endo/Exo?
q →goes out of the sys. into surr.
W→goes out of sys. and into surr.
Sign:
ONLY -
Process:
EXOTHERMIC
What is the sign of ∆E & Is it Endo/Exo?
q →goes into the system
W→goes into the system
Sign:
+
Process:
ENDOTHERMIC
What is the sign of ∆E & Is it Endo/Exo?
q →goes into the system
NO WORK IS DONE
Sign:
+
Process:
ENDOTHERMIC
