Unit 4 Chem Test!

Front 1

chemical bond

Back 1

a link between atoms that results from the mutual electrical attractions between the nuclei and valence electrons of both atoms

Front 2

ionic bond

Back 2

*a chemical bond resulting from the electrical attraction btwn. large numbers of + and - ions.
The TRANSFER of electrons
*becomes larger when combined

Front 3

covalent bond

Back 3

*a chemical bond resulting from the SHARING of electron pairs btwn two atoms
*remains the same size when share

Front 4

impure bonds

Back 4

bonds that range in btwn ionic and covalent

Front 5

ionic bonds electronegativity
range

Back 5

1.7-4.0

Front 6

polar covalent electronegativity range

Back 6

1.7-0.3

Front 7

nonpolar covalent electronegativity range

Back 7

0.0-0.3

Front 8

polar covalent bond

Back 8

a covalent bond where the united atoms have an UNEQUAL attraction for the shared electrons

Front 9

nonpolar covalent bond

Back 9

a covalent bond in which the bonding electrons are shared EQUALLY by bonded atoms with a resulting balanced distribution of charge.

Front 10

metallic bonds

Back 10

metals give up electrons but unlike ionic bonds give up an e- and then share them equally

Front 11

ionic compound

Back 11

composed of positive and negative ions combined so that the positive and negative charges are equal

Front 12

formula unit

Back 12

simplest collection of atoms from which a compound's formula can be established

Front 13

lattice energy

Back 13

the energy released when one mole of of an ionic crystalline compound is formed from gaseous ions
*larger the energy released the STRONGER THE BOND

Front 14

molecule

Back 14

the smallest unit quantity of matter which can exist by itself and retain all the properties of the original substance

Front 15

diatomic molecules

Back 15

a molecule made up of two atoms

Front 16

molecular compound

Back 16

a chemical compound whose simplest units are molecules
*made up of COVALENT bonds

Front 17

chemical formula

Back 17

indicates the relative number of each kind of atom in a compound using symbols and subscripts

Front 18

molecular formula

Back 18

indicates the relative number of each kind of atom in a MOLECULAR COMPOUND using symbols and subscripts

Front 19

bond energy

Back 19

the energy required to break a chemical bond and form neutral atoms
*units are kj/mol

Front 20

bond length

Back 20

the average distance btwn. two bonded atoms

Front 21

octet rule

Back 21

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

Front 22

expanded valence

Back 22

when elements have more than 8 in their outer shell

Front 23

unshared pair

Back 23

*also called lone pairs
*a pair of electrons that is not involved in bonding but instead belongs exclusively to one atom

Front 24

structural formula

Back 24

indicates the kind, number, arrangement, and bonds, but not the unshared pairs of the atoms in a molecule.

Front 25

isomers

Back 25

compounds that have the smae formula but a different structure

Front 26

single bond

Back 26

sharing a single pair of electrons

Front 27

double bond

Back 27

sharing two pairs of electrons

Front 28

triple bond

Back 28

sharing three pairs of electrons
*the strongest and hardest bond to break(as compared to single and double)

Front 29

covalent networking bonds

Back 29

a continous 3-D network of several different atoms

Front 30

polyatomic ions

Back 30

a charged group of covalently bonded atoms

Front 31

resonance

Back 31

refers to the bonding in molecules that cannot be correctly represented by a single lewis structure
*occurs with double and triple bonds

Front 32

central atom

Back 32

written first in the formulas
Ex. S=C=S
Carbon is central atom
Formula--CS2

Front 33

NM+NM=

Back 33

covalent bond

Front 34

M+M=

Back 34

metallic bond

Front 35

M+NM=

Back 35

ionic bond

Front 36

Electrons are delocalized?

Back 36

*electrons are free to move
*highly mobile

Front 37

Metallic bond def.

Back 37

a chemical bond resulting from the attraction between metal atoms and surrounding mobile electrons

Front 38

heat of vaporization

Back 38

amount of heat needed to change a metal from a solid to a gas

Front 39

VSEPR theory

Back 39

describes where the bonded atoms are in realation to one another. used for predicting molecular geometry

Front 40

VSEPR stands for...

Back 40

Valence Shell Electron Pair Repulsion

Front 41

VSEPR theory states...

Back 41

repusion btwn the set of valence level electron pairs surrounding an atom causes these sets to be oriented as far apart as possible.

Front 42

Hybridization

Back 42

the mixing of two or more atomic orbitals of similar energies on the same atom to produce new orbitals of equal energy.

Front 43

Hybrid orbitals

Back 43

orbitals of equal energy produced by the combination of two or more orbitals on the same atom.

Front 44

AB2

Back 44

linear

Front 45

AB2E

Back 45

bent

Front 46

AB3

Back 46

trigonal planar

Front 47

AB4

Back 47

tetrahedral

Front 48

AB3E

Back 48

trigonal pyramidal

Front 49

AB2E2

Back 49

bent

Front 50

AB5

Back 50

trigonal bipyramidal

Front 51

AB6

Back 51

octahedral

Front 52

intermolecular forces

Back 52

the forces of attraction between molecules

Front 53

dipole

Back 53

equal but opposite charges separated by a short distance. always points toward the more electronegative

Front 54

dipole-dipole forces

Back 54

forces of attraction between polar molecules

Front 55

induction

Back 55

a polar molecule can induce a dipole in a non-polar molecule.

Front 56

hydrogen bonding

Back 56

an intermolecular attraction btwn a hydrogen atom and an unshared pair of electrons on a strongly electronegative atom in another molecule

Front 57

London Dispersion Forces

Back 57

intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles and induced dipoles