Thermochemistry Quiz 1 Flashcards
which has more potential energy: a rock on top of a cliff or a rock at the bottom of the cliff
the rock on top
what is the second law of thermodynamics
energy flows from a higher define temperature to a lower temperature until an intermediate, equilibrium temperature is reached
state change term for solid to gas
sublimation
is energy absorbed or released when changing from a gas to a solid
released
define chemical change
a change resulting in new chemical arrangement of atoms to form different chemical substances
define nuclear change
a change which causes a change to the composition of an atom’s nucleus
what state is vibrational motion mostly present in
solid
state change term for gas to liqud
condensation
define heat/thermal energy
the total of the kinetic energy of all the particles in a sample of matter
define rotational motion
a slipping and sliding or spinning motion where the molecule can rotate in and around the axis
state change term for liquid to gas
evaporation or vaporization
what does c stand for and what are its units
specific heat capacity in J/g(degree)C or kJ/kg(degree)C
is energy absorbed or released when changing from a liquid to gas
absorbed
is energy absorbed or released when changing from a gas to a liquid
released
what type of energy vibrational motion, rotational motion and translational motion
kinetic
define intramolecular force
the relatively strong bonds and forces of attractive or repulsion within or inside a particle
what does m stand for and what are its units
mass in g or kg
define translational motion
a type of straight line motion where all points of a body move uniformly in a singe direction and only change direction when collisions occur
define exothermic change
a change that releases energy and causes warming up of the surroundings
potential energy calculation
(delta)H = nH
what do r subscripts represnt
refers to any type of reaction
define endothermic change
a change that absorbs energy, causing cooling of the surroundings
what state is translational motion mostly present in
gaseous
define matter
anything that has mass and occupies space
what does H stand for and what are its units
molar enthalpy change in J/mol or kJ/mol
what does (delta)T stand for and what are its units
change in temperate, degrees Celsius
what does (delta)H stand for and what are its units
change in enthalpy measured in J or kJ
define physical change
a change to the physical properties of a substance but the chemical composition is unchanged
define potential energy
a stored form of energy dependent on the relative positions of particles in a system
whats the first law of thermodynamics also known as
the law of conservation of energy
what state is rotational motion mostly present in
liquid
kinetic energy calculation
Q = mc(delta)T
what type of energy is intramolecular force and intermolecular force
potential
define temperature
the average of the kinetic energy of particles in a sample of matter
state change term for liquid to solid
freezing or solidification
what does n stand for and what are its units
quantity of substance in chemical amount, measured in moles
state change term for solid to liquid
melting or fusion
define calorimeter
the tool or equipment used to measure energy changes
what is the first law of thrermodynamics
energy can never be created or destroyed, only transferred form one place to another or changed from one type to another
what does Q stand for and what are its units
thermal or heart, measured in J or kJ
define intermolecular force
the relatively weak forces of attraction and repulsion between, outside and surrounding particles of a type of matter, AKA the energy that attracts one particle to the surrounding ones
state change term for gas to solid
deposition
define energy
the system’s ability to do work or to change
is energy absorbed or released when changing from a liquid to a solid
released
define kinetic energy
a form of energy related to motion or change and that can be seen
is energy absorbed or released when changing from a solid to a gas`
absorbed
define calorimetry
the study and process of measuring the quantities of energy involved in changes within an isolated system
is energy absorbed or released when changing from a solid to a liquid
absorbed
where are intramolecular forces most typically present
covalent bonds
define enthalpy
the total potential energy within a system at constant pressure, specifically of chemical changes or reactions
define vibrational motion
a type of movement where molecules/particles are fixed in one place while moving back and forth, jiggling or oscillating
whats the formula calculate efficiency
% efficency = energy output/energy input x 100%
