AP Midterm Flashcards

8615738766	matter	anything that has mass and takes up space	0
8615740829	atoms	the building blocks of matter	1
8615750578	substance	has distinct properties + composition that does not vary from sample to sample	2
8615752063	element	a substance which can not be decomposed to simpler substances	3
8615752498	compound	a substance which can be decomposed to simpler substances	4
8615754776	Law of Constant Composition	Compounds have a definite composition- the relative # of atoms of each element in compound= same in any sample	5
8615763423	Mixtures	exhibit the properties of the substances that make them up	6
8615761840	Homogeneous Mixture/Solution	Mixture that has the same composition throughout the sample	7
8615764930	Heterogeneous Mixture	mixture that can vary in composition throughout a sample	8
8615768644	Physical Properties	can be observed without changing a substance into another substance (i.e. BP, MP, density, mass, volume) - do not change the composition of the substance	9
8615770325	Chemical Properties	can only be observed when a substance is changed into another substance (i.e. flammable, corrosive, reactivity w/ acid) - result in new substances (combustion, oxidation, decomposition)	10
8615775844	Intensive Properties	independent of the amount of the substance that is present (i.e. density, BP, color)	11
8615776605	Extensive Properties	depend upon the amount of the substance present (i.e. mass, volume, energy)	12
8615785568	Physical Change	converting between states of matter (solid, liquid, gas)	13
8615789007	mass	measure of the amount of material in an object	14
8615824282	Law of Conservation of Mass	total mass of substances present at the end of a chemical process= mass of substances present before reaction	15
8615835169	atomic number	number of protons of an element (subscript before the symbol)	16
8615844166	mass number	total number of protons + neutrons in the nucleus of an atom (superscript before the symbol)	17
8615848926	isotopes	atoms of the same element with different masses b/c different # of neutrons, but same protons	18
8615851784	atomic weight	average mass found using all isotopes of an element weighted by their relative abundances Atomic Weight = Ʃ [(isotope mass) × (fractional natural abundance)]	19
8615856373	Periods	rows of periodic table	20
8615856374	Groups	columns of periodic table - elements in same column have similar chemical properties	21
8615866037	Empirical Formulas	lowest whole-number ratio of atoms of each element in a compound	22
8615868965	Molecular Formulas	exact number of atoms of each element in a compound	23
8615871933	Cation	ion formed when electrons are lost	24
8615871935	Anion	ion formed when electrons are gained	25
8615874092	ionic compound	formed between metals and nonmetals	26