Unit 5

Question 1

a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together.

Answer 1

Chemical Bond

Question 2

forms from the transfer of valence electrons. This forms between cations and anions (metals and nonmetals). Compounds with this type of bond have high melting points and are hard and brittle.

Answer 2

Ionic Bond

Question 3

forms when valence electrons are shared between two or more nonmetals (usually nonmetals or metalloids).

Answer 3

Covalent (molecular) Bond

Question 4

bonds in which there is an uneven distribution of electrical charge. These compounds are soluble in water. (ex. H2O and NH3) They are not symmetrical.

Answer 4

Polar Covalent Bonds

Question 5

bonds in which there is an even distribution of charge. (ex. carbon tetrachloride, CCl4) They are not soluble in water.

Answer 5

Nonpolar Covalent Bonds

Question 6

charged particles. These are atoms that have either lost or gained valence electrons. They participate in the bonding of metals and nonmetals.

Answer 6

Ions

Question 7

positive ions (mostly metals). These form when an atom loses its valence electrons.

Answer 7

Cations

Question 8

negative ions (mostly nonmetals). These form when an atom gains valence electrons.

Answer 8

Anions

Question 9

a neutral group of atoms, nonmetals, held together by covalent bonds.

Answer 9

Molecule

Question 10

a chemical compound whose simplest units are molecules (ex. NH3)

Answer 10

Molecular Compound

Question 11

indicates the relative number of each atom in a compound using the element symbols and numerical subscripts (ex. sodium sulfate = Na2SO4)

Answer 11

Chemical Formula

Question 12

same as a chemical formula, but contains nonmetals only.

Answer 12

Molecular Formula

Question 13

Start with “hydro-“ and end with “-ic” and acids, when naming.

Answer 13

Binary Acids

Question 14

When naming:
If the anion ends in “-ite” and the acid ends in “-ous” and then add the word acid.
If the anion ends in “-ate” and the acid ends in “-ic” and then add the word acid.

Answer 14

Ternary Acids

Question 15

determining the percentage of each element found in a compound

Answer 15

Percent Composition

Question 16

compounds, usually salts, that have water physically attached to them. When these compounds are heated, the water evaporates leaving behind the anhydrous salt.

Answer 16

Hydrates

Question 17

without water

Answer 17

Anhydrous

Question 18

a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample you have. Sodium chloride, for example, is always NaCl, not NaCl2 or some other combination

Answer 18

Law of Definite Proportions

Question 19

If two or more compounds are composed of the same elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers.

Answer 19

Law of Multiple Proportions

Question 20

the simplest whole-number ratio of a compound

Answer 20

Empirical Formula

Question 21

the actual formula of a molecular compound

Answer 21

Molecular Formula

Question 22

the mixing of orbitals or two or more orbitals of similar energies into orbitals of equal energy.

Answer 22

Hybridization

Question 23

Compounds will _________ their molecular orbitals when bonding to form bonds that have specific angles. This will give that molecule a particular, identifiable shape that gives that compound its specific properties.

Answer 23

rearrange

Question 24

forces other than bonds that are found between atoms

Answer 24

Intermolecular Forces

Question 25

found between polar molecules only. They are short-range forces and their compounds usually have very high boiling points (ex. BrF)

Answer 25

Dipole-Dipole Forces

Question 26

forms between hydrogen bond/force such as fluorine and oxygen. These compounds, like water, have very high boiling points.

Answer 26

Hydrogen Force

Question 27

results from the constant motion of electrons that create an instantaneous dipole. These forces increase as the size of the compound increases. Br2 has greater forces than Cl2.

Answer 27

London Dispersion

Question 28

a “bond” that occurs between metals only and is the result of the attraction of the protons in one atom for the electrons in another atom. This produces a “sea” of electrons around the alloy which allows that alloy to conduct an electrical current. It varies with the number of valence electrons in the “se” and the nuclear charge of the atom.

Answer 28

Metallic Bonds

Question 29

the energy required to break a chemical bond. The more bonds found between two elements, the harder they are to break.

Answer 29

Bond Energy

Question 30

Chemical compounds tend to form so that each atom, by gaining, losing, or sharing valence electrons, has an octet of electrons in its las (highest) energy level.

Answer 30

The Octet Rule

Question 31

uses dots to symbolize the valence electrons in an atom. One pair of electrons is symbolized by one line. Two pair equals two lines.

Answer 31

Lewis Structures

Question 32

states that the repulsion between the sets of pairs of valence electrons surrounding an atom can cause sets of electrons to be placed as far apart as possible. (remember Hund’s rule?)

Answer 32

VSEPR Theory (Valence-Shell Electron Pair Repulsion)