IB Chemistry Chapter 1 Terms

Scientific Method
the process of studying natural phenomena, involving observations, forming laws and theories, and testing of theories by experimentation
a quantitative observation
one or more assumptions put forth to explain the observed behavior of nature
a set of assumptions put forth to explain some aspect of the observed behavior of matter
a set of assumptions put forth to explain observed behavior of matter. It usually involves assumptions about the behavior of individual atoms or molecules.
Natural Law
a statement that expresses generally observed behavior
Law of Conservation of Mass
mass is neither created nor 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 of a measurement
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
Exponential Notation
expresses a number as N x 10^M, a conventional method for representing a very large or very small number and for easily indicated the number of significant figures
Unit Factor Method
an equivalence statement between units used for converting from one unit to another
Dimensional Analysis
another term for “unit factor method”
a property of matter representing the mass per unit volume
the material of the universe
States (of Matter)
the three different forms in which matter can exist; solid, liquid, and gas
Homogeneous Mixture
a mixture having visibly indistinguishable parts
Heterogeneous Mixture
a mixture having visibly distinguishable parts
a homogeneous mixture
Pure Substance
a substance with constant composition
Physical Change
a change in the form of a substance, but not in its chemical composition; chemical bonds are not broken in a physical change
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
a type of chromatography that employs a strip of porous paper, such as filter paper, for 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 the relative numbers of reactant and product molecules
a substance that cannot be decomposed into simpler substances by chemical or physical means