Chapter 3 - Molecules, Compounds, and Chemical Equations

Question 1

In a compound, elements combine in…

Answer 1

fixed, definite proportions.

Question 2

In a mixture, elements can mix in…

Answer 2

any proportions whatsoever.

Question 3

A hydrogen-oxygen mixture can have ___ proportions of hydrogen and oxygen gas. Water, by contrast, is composed of water molecules that always contain two hydrogen atoms to everyone one oxygen atom. Water has a ______ proportion of hydrogen to oxygen.

Answer 3

any, definite.

Question 4

Ionic bonds occur between ______ and _______, and involve the ______ of electrons from one atom to another.

Answer 4

metals and nonmetals, transfer.

Question 5

Covalent bonds occur between…, and involve the _______ of electrons between two atoms

Answer 5

two or more nonmetals, sharing.

Question 6

Metals have a tendency to lose electrons, and nonmetals have a tendency to gain them, therefore, when a metal interacts with a nonmetal, it can ______ one or more of its electrons to the nonmetal.

Answer 6

transfer

Question 7

What is the result of an ionic bond?

Answer 7

Ionic compound.

Question 8

An ionic compound, which in the solid phase, is composed of a _______, a regular _____-___________ ______ of alternating ______ and _______

Answer 8

lattice, three-dimensional array of alternating cations and anions.

Question 9

When a nonmetal bonds with another nonmetal, neither atom transfers its electron to the other. Instead, the bonding atoms _____ some of their electrons. The shared electrons have _____ potential energy than they would in the isolated atoms because they interact with the nuclei of both atoms.

Answer 9

share, lower

Question 10

Covalently bound atoms compose a _______. Each molecule is independent of the others - the molecules are themselves not covalently bound to one another. Therefore, we call covalently bonded compounds ________ _______.

Answer 10

molecule, molecular compounds.

Question 11

The lowest potential energy occurs when the negative charge lies _______ the two positive charges because in this arrangement the negative charge can interact with ____ positive charges.

Answer 11

between, both

Question 12

In a chemical formula, what order are the elements normally listed?

Answer 12

The more metallic (or more positively charged) elements first, followed by the less metallic (or more negatively charged) elements.

Question 13

What’s the difference between empirical formula and molecular formula?

Answer 13

Empirical formula gives the relative number of atoms in a compound (so the simplified formula of the molecular formula), and the molecular formula gives the actual number of atoms of each element in a molecule of a compound.
Ex:
H2O2 –> molecular formula
HO –> empirical formula

Question 14

A double bond is generally ______ and shorter than a single bond.

Answer 14

stronger

Question 15

A single bond corresponds to ___ shared electron pair, while a double bond corresponds to ___ shared electron pairs.

Answer 15

one, two

Question 16

A ________ formula uses lines to represent ______ bonds and shows how atoms in a molecule are connected or bonded to each other.

Answer 16

structural formula, covalent

Question 17

White represents ________

Answer 17

Hydrogen

Question 18

Black represents ________

Answer 18

Carbon

Question 19

Blue represents ________

Answer 19

Nitrogen

Question 20

Red represents ________

Answer 20

Oxygen

Question 21

Yellow represents ________

Answer 21

Sulfur

Question 22

Green represents ________

Answer 22

Chlorine

Question 23

A _______ model is a more accurate and complete way to specific a compound.

Answer 23

molecular

Question 24

Which model represents atoms as balls and chemical bonds as sticks?

Answer 24

Ball-and-stick molecular model

Question 25

Elements may be their _____ or ________. | Compounds may be either ________ or _____.

Answer 25

atomic or molecular. | ionic or molecular.

Question 26

______ elements exist in nature with single atoms as their basic units.

Answer 26

Atomic

Question 27

________ elements do not normally exist in nature with single atoms as their basic units; instead, they exist as molecules - two or more atoms of the element bonded together.

Answer 27

Molecular

Question 28

Most molecular elements exist as ________ molecules.

Answer 28

diatomic

Question 29

Molecular compounds are usually composed of two or more _________ bonded nonmetals.

Answer 29

covalently

Question 30

______ compounds are composed of cations (usually a metal) and anions (usually one or more nonmetals) bound together by ______ bonds.

Answer 30

Ionic

Question 31

The basic unit of an ionic compound is the _______ ____, the smallest, electrically neutral collection of ions.

Answer 31

formula unit

Question 32

Most polyatomic ions are _______, anions containing oxygen and another element.

Answer 32

oxyanions.

Question 33

Prefixes "hypo-" meaning ____ ____, and "per-" meaning ____ ____.

Answer 33

less than, more than. So CLO^-1 is hypochlorite (less oxygen than chlorite) and CLO4^- is perchlorate (more oxygen than chlorate).

Question 34

Some ionic compounds - called ______ - contain specific number of water molecules associated with each formula unit.

Answer 34

hydrates

Question 35

Mono =

Answer 35

1

Question 36

Di =

Answer 36

2

Question 37

Tri =

Answer 37

3

Question 38

Tetra =

Answer 38

4

Question 39

Penta =

Answer 39

5

Question 40

Hexa =

Answer 40

6

Question 41

Hepta =

Answer 41

7

Question 42

Octa =

Answer 42

8

Question 43

Nona =

Answer 43

9

Question 44

Deca =

Answer 44

10

Question 45

If there is only one atom of the first element in the formula, the prefix "____" is normally omitted.

Answer 45

mono-

Question 46

Name N2O

Answer 46

Dinitrogen monoxide

Question 47

Define acids.

Answer 47

Molecular compounds that release hydrogen ions (H+) when dissolved in water.

Question 48

Acids are composed of _______, usually written first in their formula, and one or more _______, written second..

Answer 48

hydrogen, nonmetals

Question 49

What does (aq) mean?

Answer 49

Aqueous - dissolved in water

Question 50

Binary acids are composed of ______ and a ________

Answer 50

hydrogen and a nonmetal

Question 51

What is the form for naming a binary acid?

Answer 51

hydro + (base name of nonmetal)(-ic) + acid

Question 52

Name HCL(aq)

Answer 52

Hydrochloric acid

Question 53

Name HBr(aq)

Answer 53

Hydrobromic acid

Question 54

What is the base name for (I) Iodine?

Answer 54

iod

Question 55

Name HI(aq)

Answer 55

Hydroiodic acid

Question 56

_______ contain hydrogen and an oxyanion (an anion contain a nonmetal and oxygen).

Answer 56

Oxyacids

Question 57

Oxyacids are a combination of one or more H+ ions with an ______

Answer 57

oxyanion

Question 58

1 carbon atom

Answer 58

meth-

Question 59

2 carbon atoms

Answer 59

eth-

Question 60

3 carbon atoms

Answer 60

prop-

Question 61

4 carbon atoms

Answer 61

but-

Question 62

5 carbon atoms

Answer 62

pent-

Question 63

6 carbon atoms

Answer 63

hex-

Question 64

7 carbon atoms

Answer 64

hept-

Question 65

8 carbon atoms

Answer 65

oct-

Question 66

9 carbon atoms

Answer 66

non-

Question 67

10 carbon atoms

Answer 67

dec-

Question 68

All carbon-carbon bonds are single covalent

Answer 68

-ane

Question 69

At least one carbon-carbon bond is double covalent, arid the rest are single covalent

Answer 69

-ene

Question 70

At least one carbon-carbon bond is triple covalent, and the rest are double covalent

Answer 70

-yne