chapter 6
breaking bonds requires energy while forming bonds releases energy
PE = mgh
KE = m(v)²/2
mass, velocity
si unit of energy is joules = kg(m²)/s²
1 cal = 4.184 j
E total = KE + PE +internal energy
internal energy is extensive
work is positive (energy added) when done ON the thermodynamic system, and negative (energy subtracted) when it’s done BY the system
work (JOULES = L.atm) = -PΔV
q = heat
positive if absorbed by / added to the system
negative is evolved / released by the system
open system is open to atmosphere
closed isn't open to atmosphere but energy can cross that boundary
isolated system isn’t open to atmosphere and nothing can cross the boundary
state function:
property of a system that depends only on present state (final and initial) and not the path
p, v, energy, t
change in internal energy = heat + work
CHECK UNITS
heat of reaction
exo -
endo +
enthalpy = u +pv
q = ΔH
change in enthalpy
ΔU = q + w = ΔH - PΔV
q = CΔt
molar heat capacity
q= mcΔt
c = specific heat
ΔH° = Eᴘ - Eʀ
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