Chapter 7

Question 1

anion

Answer 1

A negatively charged ion; that is, an ion in which the atom or group of atoms has more electrons than protons

Question 2

binary compound

Answer 2

a compound consisting of two elements; may be ionic or covalent

Question 3

bonding pair

Answer 3

a pair of electrons involved in a covalent bond. Also called a shared pair.

Question 4

Cation

Answer 4

A positively charged ion; that is, an ion in which the atom or group of atoms has fewer electrons than protons.

Question 5

Chemical bond

Answer 5

A chemical bond formed by the sharing of one or more electron pairs between two atoms

Question 6

Covalent bond

Answer 6

A chemical bond formed by the sharing of one or more electron pairs between two atoms

Question 7

Covalent compound

Answer 7

A compound containing predominantly covalent bonds

Question 8

Debye

Answer 8

The unit used to express dipole moments

Question 9

Delocalization of electrons

Answer 9

Refers to bonding electrons distributed among more than two atoms that are bonded together; occurs in species that exhibit resonance

Question 10

Dipole

Answer 10

Refers to the separation of charge between two covalently bonded atoms

Question 11

Dipole moment (μ)

Answer 11

The product of the distance separating opposite charges of equal magnitutde and the magnitude of the charge; a measure of the plarity of a bond or molecule. A measured dipole moment refers to the dipole moment of an entire molecule.

Question 12

Double bond

Answer 12

A covalent bond resulting from the shared of four electrons (two pairs) between two atoms

Question 13

Electron-deficient compound

Answer 13

A compound containing at last one atom (other than H) that has fewwer than eight valence shell electrons

Question 14

Expanded valence shell

Answer 14

Describes an atom that contains more than eight valence shell electrons

Question 15

Formal charge

Answer 15

They hypothetical charge on an atom in a covalently bonded molecule or ion; bonding electrons are counted as though they were shared equally between the two bonded atoms

Question 16

Heteronuclear

Answer 16

Consisting of different elements

Question 17

homonuclear

Answer 17

consisting of one element

Question 18

hypervalent

Answer 18

describes an atom that contains more than eight valence shell electrons

Question 19

ion

Answer 19

an atom or a group of atoms that carries an electrical charge

Question 20

ionic bonding

Answer 20

the attraction of oppositely charged ions (cations and anions) in large numbers to form a solid. Ions result from the transfer of one or more electrons from one atom or grouop of atoms to another

Question 21

ionic compound

Answer 21

a compound containing predominantly ionic bonding

Question 22

Isoelectric

Answer 22

having the same number of electrons

Question 23

Lewis acid

Answer 23

a substance that accepts a share in a pair of electrons from another species

Question 24

Lewis base

Answer 24

A substance that makes available a share in an electron pair

Question 25

Lewis formula

Answer 25

The representation of a molecule, ion, or formula unit by showing atomic symbols and only outer-shell electrons; does not represent the shape of the molecule or ion. Each bonding electron pair can be represented by a pair of dots (the Lewis dot formula) or by a dash (the Lewis dash formula)

Question 26

Lone pair

Answer 26

A pair of electrons residing on one atom and not shared by other atoms; unshared pair

Question 27

Monatomic ion

Answer 27

An ion that consissts of only one atom

Question 28

Nonpolar bond

Answer 28

A covalent bond between two atoms with the same electronegativity, so that the electron density is symmetrically distributed

Question 29

Octet rule

Answer 29

Many representative elements attain at least a share of eight electrons in their valence shells when they form molecular or ionic compounds; there are some limitations

Question 30

Polar bond

Answer 30

A covalent bond between two atoms with different electronegativeities , so that the electron density is unsymetrically distributed

Question 31

Polyatomic ion

Answer 31

An ion that consists of more than one atom

Question 32

Resonance

Answer 32

A concept in which two or more Lewis formulas for the same arrangement of atoms (resonance structures) are used to describe the bonding in a molecule or ion

Question 33

Single bond

Answer 33

A covalent bond resulting from the sharing of two electrons (one pair) between two atoms

Question 34

Triple bond

Answer 34

A covalent bond resulting from the sharing of six electrons (three pairs) between two atoms

Question 35

Unshared pair

Answer 35

A pair of electrons residing on one atom and not shared by other atoms; lone pair

Question 36

Valence electrons

Answer 36

The *s* and *p* electrons in the outermost shell of an atom