Test 3 Flashcards
absorbs moisture, can clump/get caked
hydroscopic
dried out, susceptible to hydroscopy
anhydrous
no limit, takes in water, pulls moisture
deliquescent
molecules have to touch for
convection
fluids that move
convection
spontaneous proccess
happens on its own
nonspontaneous
needs input of energy
4 types of energy for the motion of particles, KE or PE?
1) translational NRG, 2) rotational NRG, 3) vibrational NRG, 4) electronic NRG; KE
enthalpy
heat and change
entropy
nature goes towards chaos
NRG is the ability to…
do work
W=
f*d
f unit(s)
N; kg*m/s2
joule is also
kg*m2/s2
F=
m*a
1 Calorie=?calories
1000; 1 kilo
1 calorie=?joules
4.184
intermolecular forces compared to evaporation rate
weaker forces, quicker evaporation
solid to gas
sublimation
gas to solid
deposition
dynamic condition in which two opposing changes occur at equal rates in a closed system
equilibrium
pressure exerted by a vapor in equilibrium with its corresponding liquid at room temperature
equilibrium vapor pressure
temp. liquid increases = KE molecs. ____
increases
volatile
liquids that can readily evaporate and have relatively weak forces of attraction between particles
decrease in atmospheric pressure = _____ boiling point
decrease
why is water an effective cooling agent
it has a high molar enthalpy of vaporization, strong hydrogen bonds means more energy to overcome them
freezing point
temperature where the solid and liquid are in equilibrium at 1 atm
melting: ___ + ___ –>
solid + energy –> liquid
molar enthalpy of fusion
amount of heat energy needed to melt one mole of solid at the melting point
critical temperature of water
373.99 C
critical pressure of water
217.75 atm
triple point
solid, liquid, and vapor can coexist at equilibrium
critical pressure
lowest pressure a substance can be a liquid at the critical temp
critical temperature
highest temp the substance can exist in liquid state
the number of linked molecules ____ as temperature increases
decreases
water molecules in hexagonal arrangement in…
ice
what accounts for low ice density
empty spaces caused by hexagonal arrangement
what does a high molar enthalpy do
helps organisms resist dehydration and maintain homeostasis
device to measure energy absorbed or released as heat
calorimeter
measure of avg KE of particles in matter
temperature
SI unit of heat
Joules, J
quantity transferred as heat during temperature change depends on (3)
nature and mass of material changing temp and size of temperature change
specific heat
amount of energy required to raise the temp of 1g of substance by 1 degree celcius
q
energy lost or gained
products have lower enthalpy than reactants
exothermic
products have a higher enthalpy than reactants
endothermic
lower altitude=____ atmospheric pressure, ____ boiling point
higher, higher
(water) ml=; why
g; b/c density of water
why does sand get hotter in the day and colder at night than water
water has a higher specific heat capacity
on a plateau in a heating or cooling curve, the equation
q=m*deltaH (fusion or vaporization)
difference between temperature and heat
temperature measures the average kinetic energy, white heat is the total kinetic energy. heat is extensive
why doesnt water (for example) continually increase as it is heated
temperature will remain the same when going through a phase change (plateaus)
solve for ____: how much heat required…
Q
solve for ___: how much energy is required
Q
1 Calorie = kcal
1
1st law of thermodynamics
energy cannot be created nor destroyed, it can only change forms; heat lost+heat gained=0
2nd law of thermodynamics
some energy is lost as heat
meaning of the sign in front of energy values
show whether energy was lost or gained
