Chapter 5

Question 1

The compound that forms ionic bonds is an __________.

Answer 1

ionic compound

Question 2

The compound that forms covalent bonds is a __________.

Answer 2

molecular compound

Question 3

The chemical formula for an ______________ lists:

1. the type of atom present and
2. the lowest whole number ratio of atoms present

Answer 3

ionic compounds

Question 4

The chemical formula for a _______________ lists:

1. the types of atoms present and
2. the exact number of atoms present, regardless of the numbers involved.

Answer 4

molecular compound

Question 5

Unlike ionic compounds, the clustering of _____ atoms have a unique 3-D shape.

Answer 5

nonmeta

Question 6

A _______ is basically the limit of physical subdivision where a single entity retains all of the properties of the original group of molecules.

Answer 6

molecule

Question 7

_______ ______ are formed when two atoms share electrons rather than transfer or accept them.

Answer 7

Covalent bonds

Question 8

A ____________ is formed by an unequal sharing of electrons.

Answer 8

polar covalent bond

Question 9

_________ describes the affinity or attraction that the nucleus of a given atom has for a shared pair of electrons in a covalent bond.

Answer 9

Electronegativity

Question 10

_______ want electrons and therefore have relatively high electronegativities.

Answer 10

nonmetals

Question 11

______ don’t need the electrons and therefore have very low electronegativities.

Answer 11

metals

Question 12

What is the bond type when the electronegativity difference is 0?

Answer 12

pure or true covalent

Question 13

What is the bond type when the electronegativity difference is <0 - 0.4?

Answer 13

nonpolar covalent

Question 14

What is the bond type when the electronegativity difference is <0.4 - 1.5?

Answer 14

polar covalent

Question 15

What is the bond type when the electronegativity difference is <1.5 and <2.0?

Answer 15

polar covalent - between 2 nonmetals that show 3-D molecular shape

Question 16

What is the bond type when the electronegativity difference is <1.5 and <2.0?

Answer 16

ionic - between metal and nonmetal with no 3-D shape in the compound

Question 17

What is the bond type when the electronegativity difference is 2.0 or greater?

Answer 17

ionic

Question 18

When H is listed as the first element in a compound, it usually signifies that the compound is ______ to some degree.

Answer 18

acidic

Question 19

What are the 2 factors that lead to polarity and must be present before a molecule will behave as a polar species?

Answer 19

1. Polar bonds must be present in the molecule.

2. The shape of the molecule cannot be symmetrical with respect to the polar bonds.

Question 20

TRUE or FALSE:

Nonmetal atoms of the same type will often bond with each other.

Answer 20

True

Question 21

How are molecular compounds different from ionic compounds?

Answer 21

Molecules have unique 3-D shapes with atoms oriented in fixed positions in space. Ionic compounds form from a repeating lattice structure of alternating cations and anions – there is really no unique molecular structure in the ionic substance.

Question 22

A chemical formula of an ionic compound shows the _________ ratio of ions.

Answer 22

lowest whole number

Question 23

A chemical formula of a molecular compound shows the ______ number of atoms.

Answer 23

exact

Question 24

TRUE or FALSE:

Molecular compounds are very different from ionic compounds.

Answer 24

true

Question 25

If you were able to take a pure sample of water and divide it in half again and again, what would be the limit of this subdivision process where the last piece of water still behaved like water?

Answer 25

a single water molecule

Question 26

The formula for a covalent compound must describe the actual number of atoms found in one ________ of the substance.

Answer 26

molecule

Question 27

Covalent bonds result from the _______ of a _____ of electrons between atoms.

Answer 27

sharing a pair

Question 28

The valence electrons are the _______ to transfer or share in chemical bonds.

Answer 28

easiest

Question 29

Covalent bonding must involve the ______ shell electrons.

Answer 29

valence

Question 30

TRUE or FALSE: It is reasonable that the valence electrons are involved in chemical bonds since they are the outermost electrons and they must come in contact first when atoms come together.

Answer 30

true

Question 31

Do covalent bonds, formed among nonmetal atoms, tend to obey or disobey the octet rule?

Answer 31

obey

Question 32

Some chemical bonds have characteristics of both _____ and ______ bonds.

Answer 32

ionic and covalent

Question 33

Unequal sharing of electrons leads to the formation of ___________.

Answer 33

polar covalent bonds

Question 34

Who came up with the idea of electronegativity?

Answer 34

Linus Pauling

Question 35

What is the most electronegative element and what is it's value?

Answer 35

F (Fluorine) is 4.0

Question 36

Why don't noble gases have an electronegative value?

Answer 36

They have a full outer shell and don't form bonds with other elements.

Question 37

Metals have _____ electronegativities and nonmetals have ______ electronegativities.

Answer 37

low; | high

Question 38

Given the electronegativity values of the following atoms, describe the characteristic of the chemical bond formed between them: Na (0.9) and Cl (3.0)

Answer 38

NaCl is ionic at a value of 2.1 - metal with nonmetal

Question 39

The major character of a chemical bond is defined by a difference in the _________ of the atoms involved.

Answer 39

electronegativity

Question 40

Describe the characteristic of the chemical bond formed between H (2.1) and F (4.0).

Answer 40

HF - polar covalent bond at a value of 1.9 - 2 nonmetal atoms

Question 41

Describe the characteristic of the chemical bond formed between C (2.5) and O (3.5).

Answer 41

CO - polar covalent at a value of 1.0

Question 42

Under what circumstances will 2 atoms form a pure covalent bond?

Answer 42

When atoms involved are identical and have the same electronegativity.

Question 43

Polar covalent bonds with small differences in electronegativity behave a lot like __________.

Answer 43

pure covalent bonds

Question 44

Molecular structure is a strong indication that the bonds have ___________ character.

Answer 44

covalent

Question 45

Why is it hard to name covalent compounds?

Answer 45

They do not form predictable associations with other atoms and there are billions of these compounds in nature

Question 46

Which atom is listed first in a simple binary compound that is not acidic?

Answer 46

least electronegative atom

Question 47

What is the greek prefix that means three?

Answer 47

tri-

Question 48

When are the number of H atoms not included in the name of the compound?

Answer 48

When it is listed first in the formula (acidic)

Question 49

What 2 factors lead to molecular polarity?

Answer 49

the presence of polar bonds and the asymmetrical shape