Studied by 1 persondefine first law of thermodynamics
the total energy of an isolated system is constant; energy can be transformed from one form to another but can be neither created no destroyed
what is the key principle of the first law of thermodynamics
what is the key concept of the first law of thermodynamics
what is the symbol and units of the first law of thermodynamics
conservation of energy
energy
E and Joule / J
what is the conservation of energy
in a closed system, energy cannot be created or destroyed. it can only be transformed from one form to another. the energy of our universe is constant
what is a thermodynamic system is
a system [eg. beaker, earth], surroundings [eg. universe] and a system boundary
what does the first law of thermodynamics relate to
the internal energy of a system to the amount of heat added to the system and the amount of work done on the system
when is work done
when a force is applied to an object and that causes the object to move a distance
define the zeroth law
"if 2 systems are each in thermal equilibrium with a third, they are in thermal equilibrium with each other"
allows us to do experiments
key concept = temperature
symbol = T
units = K, kelvin
why is thermodynamics important
we can interconvert:
kinetic energy, chemical energy, heat, work, light, nuclear energy
applies to:
atoms and molecules, chemical bonds, photons and electrons, biology, engineering, earth science, the universe
how to draw an energy reaction coordinate diagram
see page 8 of booklet
why are chemistry, bonds and the first law important
to consider the bonds broken and formed
define an open system
can exchange heat and matter
eg = beaker, human body and cells
define a closed system
exchange only heat
eg = light bulb, solar panel
define isolated system
no exchange of heat or matter
eg = perfect thermos, bomb calorimeter
define isothermal change
has a diathermal wall [exchange heat not matter]
temperature of the system stays the same as the surroundings
is a closed system
define adiabatic change
no heat transfer
isolated system, no exchange of heat between system and surroundings
perfectly isolated system
has an adiabatic wall
transfers energy only as work
in a breitling orbiter, what type of system is the helium balloon
closed system
otherwise helium would be displaced for air
in a breitling orbiter, what type of system is the hot air balloon
open system
needs to be able to expand and lose mass
in a breitling orbiter, what type of system is the propane burner
open system
needs to exchange heat and matter
is planet earth an open, closed, or isolated system
assume closed system is not isolated → exchange heat and light
some loss of helium / hydrogen but close to negligible
Note
Flashcard