Exam 1 Flashcards
open system
matter and energy exchange can occur
ex: humans
closed system
no matter exchange
ex: insulated, sealed water bottle
isolated system
no matter or energy exchange
system + surrounding = isolated system
true isolated system is the universe
kinetic energy
relates to temperature changes
potential energy
relates to repulsion/attraction and protein conformational energy
energy is an __________ property
extensive
intensive properties
property does not change with the size of the system
“doesn’t matter how much you have”
ex: combining two bottles of water that are the same temperature; temp will stay the same (intensive) but energy stored will double (extensive)
types of heat exchange
radiation, evaporation, convection, conduction
energy transferred as heat leads to ________ motion
random
energy transferred as work leads to ________ motion
ordered
first law of thermodynamics
the total energy of the system + its surrounding is constant
alt: in closed systems, internal energy change is balanced by heat transfer and system work
internal energy goes up if the surroundings ________ on the system
do work
ideal gas equation
PV = nRT
what variables are needed to define an ideal gas system?
pressure and volume
work done by the system to the environment depends on which pressure?
external pressure, NOT internal pressure
