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energy
the capacity to do work
TERM 2
potential energy
DEFINITION 2
stored energy
TERM 3
kinetic energy
DEFINITION 3
energy of motion
TERM 4
energy is measured in ____
DEFINITION 4
calories and joules
TERM 5
I Cal
DEFINITION 5
nutritional calorie
when a bond is formed, energy is _____
released
TERM 7
when a bond is broken, energy is _____
DEFINITION 7
added
TERM 8
heat of reaction
DEFINITION 8
the energy absorbed or released in any reaction
enthalpy change
TERM 9
when energy is absorbed, reaction is _____
DEFINITION 9
endothermic
TERM 10
when energy is released, reaction is ____
DEFINITION 10
exothermic
when ^H is
positive
more energy is needed to break bonds than is released
from forming bonds
bonds broken in reactants are stronger than bonds
formed in products
reaction is endothermic
heat is absorbed
TERM 17
Ea
DEFINITION 17
activation energybarrier separating reagents and products
TERM 18
when Ea is high
DEFINITION 18
large barrier for reagents to be converted to products
slow reaction
few molecules have enough energy to reach the energy
barrier
TERM 19
when Ea is low
DEFINITION 19
more molecules are able to cross the energy barrier and
form products
faster reaction
TERM 20
^H
DEFINITION 20
the difference in energy of reagents and products
doesn't depend on Ea
energy of products - energy of reagents
transition state
at top of Eatransition between reactants and productsbond is
partially broken and partially formed
TERM 22
increase concentration
DEFINITION 22
increase reaction rate
TERM 23
increase temperature
DEFINITION 23
increase reaction rateincrease kinetic energy
TERM 24
catalyst
DEFINITION 24
a substance that speeds up the rate of a reaction by lowering
the activation energy
TERM 25
enzymes
DEFINITION 25
biological catalyst
removing reagent
> reagents
TERM 32
adding product
DEFINITION 32
> reagents
TERM 33
removing product
DEFINITION 33
> products
TERM 34
increasing temperature
DEFINITION 34
endothermic > productsexothermic > reagents
TERM 35
decreasing temperature
DEFINITION 35
endothermic > reagentsexothermic > products
increasing pressure
> side with fewer moles
TERM 37
decreasing pressure
DEFINITION 37
> side with more moles
TERM 38
k=
DEFINITION 38
pressure times volume
TERM 39
boyle's law
DEFINITION 39
for a fixed amount of gas at a constant temperature, the
pressure and the volume of a gas are inversely
relatedp1v1=p2v
TERM 40
charles' law
DEFINITION 40
for a fixed amount of gas of constant pressure, the volume of
a gas is proportional to its temperature in KelvinV1 = V2T
T
standard temperature
273 K or 0C
TERM 47
standard molar volume
DEFINITION 47
22.4 L
TERM 48
ideal gas law
DEFINITION 48
PV = nRT
TERM 49
intermolecular forces
DEFINITION 49
the attractive or repulsive forces that exist between
molecules
TERM 50
London dispersion forces
DEFINITION 50
the weak interactions due to momentary changes to electron
density of a molecule
all covalent molecules have this
the larger the molecule, the ___ the attractive
forces between the 2 molecules
larger
TERM 52
dipole dipole interactions
DEFINITION 52
the attractive forces between the 2 permanent dipoles of 2
polar molecules
molecules must be polar
TERM 53
hydrogen bonds
DEFINITION 53
the interaction between a hydrogen atom bonded to an O an
N or an F, or an O,N, or F on another molecule
high electronegativity
strongest bond
TERM 54
the stronger the intermolecular forces, the
____ the boiling and melting points
DEFINITION 54
higher
TERM 55
vapor pressure
DEFINITION 55
the pressure exerted by gas molecules in equilibrium with
the liquid phase
molecular solid
composed of individual molecules arranged regularly
TERM 62
network solid
DEFINITION 62
composed of a vast number of atoms covalently bonded
together forming sheets or 3D arrays
TERM 63
metallic solid
DEFINITION 63
a lattice of metal cations surrounded by a free moving cloud
of electrons
TERM 64
crystalline solid
DEFINITION 64
regular arrangement of particles with a repeating structure
TERM 65
amorphous solid
DEFINITION 65
no regular arrangement of its closely packed particles
heat of
fusion
the amount of energy needed to melt 1gram of a substance
TERM 67
heat of vaporization
DEFINITION 67
the amount of energy needed to vaporize 1 gram of a
substance
