30 terms

AP Chem CH 1,2

process that lies at the center of scientific inquiry
1. Make observations (take measurements)
2. Draw hypothesis
3. Perform the experiment
scientific method
set of tested hypotheses that gives an overall explanation of some natural phenomenon
natural law
generally observed behavior is formulated into this statement
law of conservation of mass
total mass is neither created nor destroyed in a chemical change
1. a number 2. a scale
quantitative measurement has 2 things
SI system
pretty universal system all over the world based on the metric system and units derived from it
commonly also called a cubic decimeter 1 L = 1 dm^3 = 1,000 cm^3 = 1,000 mL
measure of resistance of an object to a change in its state of motion
force that gravity exerts on an object
significant figures
numbers that are the certain digits and the 1st uncertain digits
the agreement of particular value with true value
the degree of agreement among being reproducible
1. random error and 2. systematic error
2 types of errors
random error
aka indeterminate error; the measurement has equal probability of being high or low
systematic error
aka determinate error; the measurement occurs in the same direction each time; either always being high or always being low
K + 273 = C
equation to convert Kelvins to Celsius
C - 273 = K
equation to convert Celsius to Kelvins
a property of matter used as "identification tag" (mass/volume)
anything that occupies space and has mass
pure substance
substance that has constant composition
process depends on differences in volatility but important method for separating components of a mixture
another method of separation used when the mixture consists of a solid and liquid
substance with constant composition that can be broken down into elements by chemical processes
chemical change
substance becomes new or has different properties with this
substances that can't be simpler broken down by any means
law of definite proportion
law discovered by Joseph Proust when he found out that a given compound always contains exactly the same proportion of elements by mass
law of multiple proportions
John Dalton discovered this law and it said that when 2 elements form a series of compounds, the ratios of the masses of the 2nd element that combine with 1 gram of the 1st element can always be reduced to small whole numbers
law of conservation of mass
law discovered by Antoine Lavoisier that said that mass is neither created nor destroyed
binary compound
compound composed of 2 elements
anions that contain an atom of a given element a different number of oxygen atoms (such as ClO-)