Chapter 6

Question 1

Ionic bond

Answer 1

A chemical bond that results from the electrical attraction between anions and cations

Question 1

What is a chemical bond?

Answer 1

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

Question 2

Covalent Bonds

Answer 2

A chemical bond that results from sharing of electron pairs between two atoms

Question 3

Nonpolar covalent Bond

Answer 3

Covalent Bond, where electrons are shared equally because their electronegativities are equal

Question 4

Polar Covalent Bond

Answer 4

A covalent bond in which the bonded atoms have an unequal attraction b/c one atom had a greater electronegativity

Question 5

When is it nonpolar covalent

Answer 5

<0.4

Question 6

When is it polar covalent?

Answer 6

0.4-1.7

Question 7

When is it ionic?

Answer 7

1.7<

Question 8

What is a molecule

Answer 8

A neutral group of atoms that are held together by covalent bonds

Question 9

Molecular compound

Answer 9

A chemical compound whose simplest units are molecules

Question 10

What is a chemical formula?

Answer 10

Indicates the relative numbers of atoms of each kind w/subscripts and elemental symbols

Question 11

Molecular Formula

Answer 11

Shows the types and numbers of atoms combined in a single molecule of a molecular compound (C6H126)

Question 12

Diatomic Molecule

Answer 12

A molecule containing only two atoms

Question 13

As two atoms come near one another, the nuclei of each atoms are attracted to the electrons of the other atoms…

Answer 13

This causes a decrease in the potential energy of the atoms

Question 14

What is bond length?

Answer 14

Average distance between two bonded atoms

Question 15

Bond energy

Answer 15

The energy required to break a chemical bond and form neutral, isolated atoms

Question 16

What is an ionic compound?

Answer 16

Composed of positive and negative ions that are combine so that the number of positive and negative charges are equal

Question 17

What is a formula unit?

Answer 17

The simplest collection of atoms from which an ionic compound’s formula can be established: NaCl

Question 18

How do ionic bonds form?

Answer 18

An atom of an element w/ low electronegativity approaches another w/ high electronegativity; high transfers an electron from the atom w/ low. Anion and cation are formed

Question 19

Polyatomic Ions

Answer 19

A covalently bonded group of atoms with a positive or a negative charge

Question 20

Intramolecular

Answer 20

Inside the molecule

Question 21

Intermolecular

Answer 21

Between 2 molecules

Question 22

Which is stronger: intramolecular or intermolecular

Answer 22

Intramolecular

Question 23

What properties reflect intermolecular forces?

Answer 23

Boiling points, melting points, viscosity, surface tension, and capillary action

Question 24

Intermolecular force: weakest to strongest

Answer 24

Dispersion Forces (or London dispersion forces) -> Dipole-Dipole forces-> Hydrogen bonding (a special dipole-dipole force)->ion-Dipole forces

Question 25

Dispersion Forces

Answer 25

Nonpolar particle can temporarily be polarized to allow dispersion force to form

Question 26

What factors affect amount of dispersion force in a molecule?

Answer 26

- # of electrons in an atoms (inc. electrons, inc. dispersion force) - size - shape of molecules w/similar masses (more compact, dec. dispersion force)

Question 27

If something is easy to polarize...

Answer 27

It has a lower boiling point

Question 28

What is a dipole

Answer 28

Partial charge: s+ means partially positive; s- means partially negative

Question 29

What are the strongest intermolecular forces between?

Answer 29

Polar molecules

Question 30

What can bond polarity create?

Answer 30

A net polarity for whole molecule or individual bonds can cancel each other

Question 31

Dipole-Dipole Interactions

Answer 31

Polar molecules have a more positive and a more negative end a dipole; opposite ends attract each other

Question 32

In Dipole-Dipole Interactions, for molecules of almost equal mass...

Answer 32

the more polar the molecule, the higher its boiling point

Question 33

When will the Dipole-Dipole Interactions or Dispersion Forces have a greater effect?

Answer 33

If two molecules are of comparable size and shape, dipole-dipole interactions will likely be the dominating force; if one molecule is much, larger, dispersion forces will likely determine its physical properties

Question 34

What is hydrogen bonding?

Answer 34

The dipole-dipole interactions experienced when H is bonded to N, O, or F are unusually strong; an attraction between a hydrogen atom attached to a highly electronegative atoms and a nearby small electron negative atom in another molecule or chemical group

Question 35

Ion-Dipole Interactions are found...

Answer 35

in solutions of ions; the strength of these forces is what makes it possible for ionic substances to dissolve in polar solvents