Chapter 11 vocabulary Flashcards
(27 cards)
thermochemistry
concerned with heat changes that occur during chemical reactions
energy
the capacity for doing work or supplying heat
chemical potential energy
energy stored within the structural units of chemical substances
heat
represented by q, is energy that transfers from one object to another because of a temperature difference between them
system
the part of the universe on which you focus your attention
surroundings
include everything else in the universe
universe
the system and its surroundings
the law of conservation of energy
states that in any chemical reaction or physical process, energy is neither created nor destroyed
endothermic process
a process that absorbs heat from the surroundings
exothermic process
a process that releases heat to its surroundings
molar heat of fusion
the heat absorbed by 1 mole of a substance melting from a solid to a liquid at constant temperature
molar heat of solidification
the heat lost when 1 mole of a liquid solidifies at a constant temperature
molar heat of vaporization
the amount of heat necessary to vaporize 1 mole of a given liquid
molar heat of condensation
the amount of heat released when 1 mole of vapor condenses
molar heat of solution
the hear change caused by dissolution of 1 mole of a substance
hess’s law of heat summation
if you add 2 or more thermochemical equations to give a final equation, then you can also add the heats of reaction to give final heat of reaction
standard heat of formation
of a compound is the change in enthalpy that accompanies the formation of 1 mole of a compound from its elements with all substances in their standard states at 25 degrees Celsius.
calorie
the quantity of heat needed to raise the temperature of 1g of water 1 degree Celsius
joule
the SI unit of heat and energy
heat capacity
the amount of heat needed to increase the temperature of an object exactly 1 degree celcius
specific heat capacity (specific heat)
the amount of heat it takes to raise the temperature of 1 g of the substance 1 degree celcius
calorimetry
the accurate and precise measurement of heat change for chemical and physical processes
calorimeter
the insulated device used to measure the absorption or release of heat in chemical or physical processes
enthalpy (H)
for systems at constant pressure, the heat content is the same as a property called enthalpy (heat changes carried out at constant pressure= same as change in enthalpy
