2 – Physical Chemistry
physical change
change that does not alter the identity of a substance
physical property
property that can be observed without changing the identity of the substance
change of state
a physical change of a substance from one state to anther
chemical change
a change in which one or more substances are converted into different substances
chemical property
the ability of a substance to undergo a change that transforms it into a different substance
chemical reaction
a reaction in which one or more substances are converted into different substances
extensive property
a property that depends on the amount of matter that is present
gas
the state of matter in which a substance has neither definite volume nor definite shape
intensive property
a property that does not depend on the amount of matter present
liquid
the state of matter in which the substance has a definite volume but an indefinite shape
product
a substance that is formed by a chemical change
precipitate
a solid that is produced as a result of a chemical change in solution that separates from the solution
reactant
a substance that reacts in a chemical change
vapor
a substances in the gaseous phases that is a liquid or a solid at room temperature
solid
the state of matter in which the substances has definite volume and shape
phase
any part of a system that has a uniform composition and properties
phase diagram
diagram that shows the conditions of pressure and temperature in which the three states of matter exist
triple point
the conditions at which all three phases exist in equilibrium with each other
sublimation
A change directly from the solid to the gaseous state without becoming liquid
deposition
the change of state from a gas directly to a solid
heat
The energy transferred between objects that are at different temperatures
temperature
A measure of the average kinetic energy of the particles in a sample of matter
heat curve
diagram that shows temperature change of substance as energy is added
specific heat
The amount of heat per gram required to raise the temperature by one degree Celsius
heat of fusion
Amount of energy required to change a substance from the solid phase to the liquid phase.
heat of vaporization
amount of heat necessary to cause a phase transition between a liquid and a gas
calorimeter
Device used to measure the heat absorbed or released during a chemical or physical process
calorimetry
The precise measurement of heat flow out of a system for chemical and physical processes
system
what is being studied for heat changes
surroundings
Everything in the universe outside of the system