Section 6.1- Energy Flashcards
all chemical reactions involve ___________ changes
energy
chemical reactions involve a reshuffling of atoms held together by forces that form
chemical bonds
the study of the flow of energy
thermodynamics
the area of chemistry that deals with applying thermodynamic principles to energy changes in chemical reactions
chemical thermodynamics
difficult to clearly define but is often considered the ability to do work
energy
one of the most fundamental scientific principles which states that energy can neither be created nor destroyed
law of conservation of energy
is energy associated with motion
kinetic energy
is energy associated with the position of an object relative to a force upon it
potential energy
symbol for internal energy
E
change in
triangle symbol
heat
Q
work
W
joule
J
enthalpy
H
specific heat
c
entropy
S
Gibbs free energy
G
the portion of the universe or the sample of matter being studied is the
system
the remainder of the universe not being studied though could be a beaker of water or the air in a laboratory
surroundings
the sum of all the possible forms of energy of all the ions, atoms, and molecules in a system
internal energy (E)
internal energy is a ______________, meaning that its value is determined only by the state of the system
state function
internal energy is ____________ of the path taken to reach a particular state and of the system’s history
independent
the equation for change in internal energy
delta E= E2 - E1 or delta E= E (final) - E (initial)
the transfer of energy between objects or systems that are in contact and are at different temperatures
heat (Q)
heat flows from _____________ to _____________ temperatures
higher to lower
may take several forms
in chemistry, all the energy exchanges between a system and its surroundings are either heat or _______
work (W)
internal energy changes described as
delta E = Q (heat) + W (work)
the mathematical statement of the first law of thermodynamics
delta E = Q + W
the practical applications of the law of conservation of energy
first law of thermodynamics
the SI unit of energy and energy transfer
joule
the older metric unit
calorie
1 cal =
4.184 J (exactly)
since the joule is a small unit, we will more often use the unit
kilojoule
