Ap Chemistry: Chapter 1

Front 1

chemistry

Back 1

the study of the compositions of substances and the ways by which their properties are related to their compositions

Front 2

matter

Back 2

anything that has mass and occupies space

Front 3

scientific method

Back 3

the observation, explanation, and testing of an explanation by additional experiments

Front 4

observation

Back 4

a statement that accurately describes something we see, hear, taste, feel, or smell

Front 5

conclusion

Back 5

a statement that is based on what we think about a series of observations

Front 6

empirical facts

Back 6

facts discovered by performing experiments

Front 7

data

Back 7

the information (in the form of physical quantities) obtained in an experiment or other experience or form references

Front 8

scientific law (law)

Back 8

a description of behavior based on the results of many experiments

Front 9

theoretical models

Back 9

a picture or a mental construction derived from a set of ideas and assumptions that are imagined to be true because they can be used to explain certain observations and measurements

Front 10

hypothesis

Back 10

a tentative explanation of the results of experiments

Front 11

theory

Back 11

a tested explanation of the results of many experiments

Front 12

atoms

Back 12

a neutral particle having one nucleus; the smallest representative example of an element

Front 13

molecule

Back 13

a neutral particle composed of two or more atoms combined in a definite ratio of whole numbers

Front 14

physical property

Back 14

a property that can be specified without reference to another substance and that can be measured without causing a chemical change

Front 15

physical change

Back 15

a change that is not accompanied by a change in chemical makeup

Front 16

chemical reaction

Back 16

a change in which new substances (products) form from starting materials (reactants)

Front 17

chemical property

Back 17

the ability of a substance, either by itself or with other substances, to undergo a change into new substances

Front 18

chemical change

Back 18

a change that converts substances into other substances; a chemical reaction

Front 19

extensive property

Back 19

a property of an object that is described by a physical quantity whose magnitude is proportional to the size or amount of the object

Front 20

intensive property

Back 20

a property whose physical quantity is independent of the size of the sample, such as density or temperature

Front 21

solid

Back 21

firm and stable in shape

Front 22

liquid

Back 22

flowing freely but that of a constant volume

Front 23

gas

Back 23

an air-like fluid substance which expands freely to fill any space available, irrespective of its quantity

Front 24

states of matter

Back 24

a physical state of a substance

Front 25

decomposition

Back 25

a chemical reaction that changes one substance into two or more simpler substances

Front 26

elements

Back 26

a substance in which all of the atoms have the same atomic number; a substance that cannot be broken down by chemical reactions into anything simpler

Front 27

chemical symbol

Back 27

a formula for an element

Front 28

compound

Back 28

a substance consisting of chemically combined atoms from two or more elements and present in a definite ratio

Front 29

pure substances

Back 29

an element or a compound

Front 30

mixtures

Back 30

any matter consisting of two or more substances physically combined in no particular proportion by mass

Front 31

homogeneous mixture

Back 31

a mixture that has only one phase and that has uniform properties throughout

Front 32

solution

Back 32

a homogeneous mixture in which all particles are on the size of atoms, small molecules, or small ions

Front 33

heterogeneous mixture

Back 33

a mixture that has two or more phases with different properties

Front 34

phases

Back 34

a homogeneous region within a sample

Front 35

grams

Back 35

0.001kg

Front 36

law of conservation of mass

Back 36

no detectable gain or loss in mass occurs in chemical reactions. Mass is conserved.

Front 37

law of definite proportions

Back 37

in a given chemical compound, the elements are always combined in the same proportion by mass

Front 38

Dalton's atomic theory

Back 38

matter consists of tiny, indestructible particles called atoms. All atoms of one element are identical. The atoms of different elements have different masses. Atoms combine in definite ratios by atoms when they form compounds.

Front 39

law of multiple proportions

Back 39

whenever two elements form more than one compound, the different masses of one element that combine with the same mass of the other are in a ratio of small whole numbers

Front 40

scanning tunneling microscope (STM)

Back 40

an instrument that enables the imaging of individual atoms on the surface of an electrically conducting specimen

Front 41

atomic mass (atomic weight)

Back 41

the average mass of the atoms of the isotopes of a given element as they occur naturally

Front 42

isotopes

Back 42

atoms of the same element with different atomic masses

Front 43

atomic mass units (amu)

Back 43

1.6606 X 10 ^ -24 g; 1/12th the mass of one atom of carbon-12.

Front 44

subatomic particles

Back 44

electrons, protons, neutrons, and atomic nuclei

Front 45

protons

Back 45

a subatomic particle with a charge of 1+ and a mass of 1.0072765 u and that is found in atomic nuclei

Front 46

neutrons

Back 46

a subatomic particle with a charge of zero, a mass of 1.0086644 u and that exists in all atomic nuclei except the hydrogen-1 isotope.

Front 47

electrons

Back 47

a subatomic particle with a charge of 1- and mass of 0.0005486 u and that occurs outside an atomic nucleus

Front 48

nucleus

Back 48

the hard, dense core of an atom that holds the atom's protons and neutrons

Front 49

nucleons

Back 49

a proton or neutron

Front 50

positive charge

Back 50

a type of electrical charge possessed by certain particles such as the proton

Front 51

negative charge

Back 51

a type of electrical charge possessed by certain particles such as the electron

Front 52

atomic number (Z)

Back 52

the number of protons in a nucleus

Front 53

mass number

Back 53

the numerical sum of the protons and neutrons in an atom of a given isotope

Front 54

periodic table

Back 54

a table in which symbols for the elements are displayed in order of increasing atomic number and arranged so that elements with similar properties lie in the same column (group)

Front 55

groups

Back 55

a vertical column of elements in the periodic table

Front 56

period

Back 56

a horizontal row of elements in the periodic table

Front 57

representative elements (main group elements)

Back 57

an element in one of the A-groups in the periodic table

Front 58

transition elements

Back 58

the elements located between Groups IIA and IIIA in the periodic table

Front 59

lanthanide elements

Back 59

elements 58-71

Front 60

actinide elements

Back 60

elements 90-103

Front 61

alkali metals

Back 61

the Group IA elements (except hydrogen)

Front 62

alkaline earth metals

Back 62

the Group IIA elements

Front 63

noble gases

Back 63

Group VIIIA in the periodic table

Front 64

halogens

Back 64

Group VIIA in the periodic table

Front 65

metalloids

Back 65

elements with properties that lie between those of metals and nonmetals, and that are found in the periodic table around the diagonal line running form B to At

Front 66

malleability

Back 66

a metal's ability to be hammered or rolled into thin sheets

Front 67

ductility

Back 67

a metal's ability to be drawn or stretched into wire

Front 68

nonmetal

Back 68

a non-ductile, non-malleable, nonconducting element that tends to form negative ions more readily than positive ions and whose oxide is likely to show acidic properties

Front 69

semiconductors

Back 69

a substance that conducts energy weakly