30 terms

AP Chemistry Chapter 1

Zumdah; Sixth Edition
Scientific method
the process of studying natural phenomena, involving observations, forming laws and theories, and testing of theories by experimentation
a quantitative description that includes both a number and a unit
a proposed explanation for an observation
a set of tested hypotheses that gives an overall explanation of some natural phenomenon
natural law
a statement that expresses generally observed behaviour
law of conservation of mass
mass is neither created or destroyed
SI system
International System of units based on the metric system and units derived from the metric system
the quantity of matter in an object
the force exerted on an object by gravity
the characteristic that any measurement involves estimates and cannot be exactly reproduced
significant figures
the certain digits and the first uncertain digit of a measurement
the agreement of a particular value with the true value
the degree of agreement among several measurements of the same quantity; the reproducibility
random error
an error that has an equal probability of being high or low
systematic error
an error that always occurs in the same direction
the material of the universe
states of matter
the three different states of matter - solid, liquid, gas
homogeneous solution
an equilibrium system where all reactants and products are in the same phase
heterogeneous solution
an equilibrium involving reactants and/or products in more than one phase
a homogeneous mixture
pure substance
a substance with constant composition
physical change
a change in the form of the substance, but not in its chemical composition: chemical bonds are not broken
a method for separating the components of a liquid mixture that depends on differences in the ease of vaporization of the components
a method for separating the components of a mixture containing a solid and a liquid
the general name for a series of methods for separating mixtures by employing a system with a mobile phase and a stationary phase
paper chromatography
Employs a strip of porous paper such as filter paper as the stationary phase
a substance with constant composition that can be broken down into elements by chemical processes
chemical change
the change of substances into other substances through a reorganization of atoms
a substance that cannot be decomposed into simpler substances by chemical or physical means