Stenberg Basic Chemistry Unit 2

Front 1

anion

Back 1

a negative ion

Front 2

halogens

Back 2

the elements of Group 17 (fluorine, chlorine, bromine, iodine, and astatine)

Front 3

alkaline-earth metals

Back 3

the elements of Group 2 (beryllium, magnesium, calcium, strontium, barium, and radium)

Front 4

periodic table

Back 4

an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall in the same column, or group

Front 5

Henry Moseley

Back 5

organized the periodic table by atomic number rather than atomic mass

Front 6

isotope

Back 6

an atom of the same element that has a different mass

Front 7

John Dalton

Back 7

in 1808, proposed the first comprehensive theory of the atom

Front 8

noble gases

Back 8

group 18 elements (helium, neon, argon, krypton, xenon, and radon)

Front 9

electron configuration

Back 9

the arrangement of electrons in an atom

Front 10

orbital

Back 10

a three-dimensional region around the nucleus that indicates the probable location of an electron

Front 11

Niels Bohr

Back 11

created a model of the atom in which the electrons were found at fixed orbits around the nucleus

Front 12

frequency

Back 12

the number of waves that pass a given point in a specific time, usually one second

Front 13

molar mass

Back 13

the mass of one mole of a pure substance

Front 14

law of conservation of mass

Back 14

mass is neither created nor destroyed

Front 15

atomic number

Back 15

the number of protons in the nucleus of each atom of that element

Front 16

Ernest Rutherford

Back 16

conducted the gold foil experiment that led to the discovery of the nucleus

Front 17

atom

Back 17

the smallest particle of an atom that retains the chemical properties of that element

Front 18

covalent bonding

Back 18

chemical bonding that results from the sharing of electron pairs between two atoms

Front 19

molecule

Back 19

a neutral group of atoms that are held together by covalent bonds

Front 20

octet rule

Back 20

chemical compounds tend to form so that each atom, by gaining, losing, or sharing electrons, has an octet of electrons in its highest occupied energy level

Front 21

valence electrons

Back 21

electrons available to be lost, gained, or shared in an atom

Front 22

metallic bonding

Back 22

chemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons

Front 23

malleability

Back 23

ability to be hammered into thin sheets

Front 24

intermolecular forces

Back 24

forces of attraction between different molecules

Front 25

polyatomic ion

Back 25

a charged group of covalently bonded atoms