Chemical Bonding

Question 1

In ionic bonding, one or more electrons from an atom with a ____ ionization energy are transferred to an atom with a greater __ ___ and the resulting ions are held together by _____ ___.

Answer 1

lower, electron affinity, electrostatic forces

Question 2

Ionic bonds happen between two atoms with ___ ___ in their ____, and there is a complete transfer of electrons from the ___ electronegative to ____ electronegative atom. For this transition to occur, the difference in electronegativity must be greater than ___ on the ____ scale.

Answer 2

large differences, electronegativities, less, more, 1.7, pauling

Question 3

Ionic compounds form ___ ___ consisting of ____ of positive and negative ions in which the attractive forces between ions of opposite charge are ____, while the repulsive forces between ions of like charge are ____. They therefore have high ___ and ___ points due to the strong electrostatic forces between the ions. They can also conduct electricity in the ___ and __ states, though not in the solid state.

Answer 3

crystal lattices, arrays, maximized, minimized, melting, boiling, liquid, gaseous

Question 4

When two or more atoms with similar electronegativities interact, the energy required to form ions is ___ than the energy that would be released upon the ___ of an ionic bond. Thus atoms ____ electrons. The binding force between the two atoms results from the ____ that each electron of the shared pair has for the two positive ___. Covalent bonds generally contain discrete ___ ___ with __ __ ___. Consequently they have low __ ___ and do not conduct electricity.

Answer 4

greater, formation, share, attraction, nuclei, molecular units, weak intermolecular forces, melting points

Question 4

The number of shared electron pairs between two atoms

Answer 4

bond order

Question 5

The average distance between the two nuclei of the atoms involved in a covalent bond

Answer 5

bond length

Question 6

the energy required to separate two bonded atoms

Answer 6

bond energy

Question 7

In general, the central atom in the lewis structure is the least ____ atom. ___ and the ___ occupy the end positions

Answer 7

electronegative, hydrogen, halogens

Question 8

Formal charge is equal to

Answer 8

valence electrons - (# of bonded electron pairs - # of non bonding electrons)

Question 9

A -__ __ is one of two or more lewis structures for a single molecule unable to be described fully with only one lewis structure. The actual molecules exists as a ___ of the structures. The more ___ the structure, the more that structure contributes to the character of the resonance ___. This would be the compound with no __ __ on any of the component atoms. Or a structure in which negative formal charges are placed on more ____ atoms.

Answer 9

resonance structure, hybrid, stable, hybrid, formal charges, electronegative

Question 10

Atoms found in or beyond the __ ___ can have more than eight valence electrons since some of the valence electrons may occupy ___ ___.

Answer 10

third period, d orbitals

Question 11

Polar covalent bonding occurs between atoms with ___ differences in electronegativity, generally in the range of ___ to ___ pauling units

Answer 11

small, 0.4,1.7

Question 12

In a coordinate covalent bond, the shared electron pair comes from the -__ __ of one of the atoms. These are typically found in lewis _____ ___.

Answer 12

lone pair, acid-base compounds

Question 13

a compound that can accept an electron pair to form a covalent bond

Answer 13

lewis acid

Question 14

a compound that can donate an electron pair to form a covalent bond

Answer 14

lewis base

Question 15

The bond angle will depend on the ____ electrons, which create additional ___, pushing any ___ ___ slightly closer together

Answer 15

nonbonding, repulsion, bonding pairs

Question 16

A molecule with 2 electron pairs and 0 nonbonding pairs will be a ____ shape, with a bond angle of ____

Answer 16

linear, 180

Question 17

A molecule with 3 electron pairs and 0 nonbonding pairs will be a ____ shape, with a bond angle of ____

Answer 17

trigonal planar, 120

Question 18

A molecule with 4 electron pairs and 0 nonbonding pairs will be a ____ shape, with a bond angle of ____

Answer 18

tetrahedral, 109.5

Question 19

A molecule with 4 electron pairs and 1 nonbonding pair will be a ____ shape, with a bond angle of ____

Answer 19

trigonal pyramidal, 107

Question 20

A molecule with 4 electron pairs and 2 nonbonding pairs will be a ____ shape, with a bond angle of ____

Answer 20

bent, 104.5

Question 21

A molecule with 5 electron pairs and 0 nonbonding pairs will be a ____ shape, with a bond angle of ____

Answer 21

trigonal bipyramidal, 90, 120, 180

Question 22

A molecule with 5 electron pairs and 0 nonbonding pairs will be a ____ shape, with a bond angle of ____

Answer 22

octahedral, 90, 180

Question 23

If the orientation of the __ ___ are such that they cancel out, they will result in a ___ molecule. If they do not cancel out it will be a ___ molecule

Answer 23

bond dipoles, nonpolar, polar

Question 24

When two atomic orbitals with the same sign overlap

Answer 24

bonding orbital

Question 25

When two atomic orbitals with different signs overlap

Answer 25

antibonding orbital

Question 26

When two orbitals of different atoms overlap head to head

Answer 26

sigma bond

Question 27

When parallel p orbitals interact

Answer 27

pi bond

Question 28

dipole-dipole and london dispersion forces

Answer 28

van der waals forces

Question 29

In d-d interactions, polar molecules tend to orient themselves such as the ___ region of one molecule is close to the ___ region of another molecule. An attractive ___ force is formed between them. These interactions are present in ___ and ___ phases, but are negligible in ____ phase because the molecules are much further apart. Polar species tend to have higher ___ ___ than the nonpolar species of comparable molecular weight

Answer 29

positive, negative, dipole, liquid, solid, gaseous, boiling points

Question 30

Hydrogen bonding is a specific, __ form of d-d interactions. When hydrogen is bound to ___, ___ or ___, hydrogen carries little of the __ ___ of the covalent bond. It can interact with the partial ___ charge of nearby molecules also bonded to hydrogen. Substances with H bonding have high ___ ___. This type of bonding is important in the behaviour of ___, ___, __ and __ ____

Answer 30

strong, nitrogen, fluorine, oxygen, electron density, negative, boiling points. water, amines, alcohols, carboxylic acids

Question 31

The bonding electrons in a covalent bond with be located ____ throughout the ____. This permits unequal sharing of electrons, causing rapid ___ and ___ of the electron cloud and formation of short lived ___. These interact with the electron clouds of neighboring molecules, inducing the formation of more dipoles. These are called ____, and are generally ____. They do not extend over long ___, and are most important when molecules are _____ together.

Answer 31

randomly, orbital, polarization, counterpolarization, dipoles, LDF, weak, distances, close

Question 32

The strength of LDFs depends on how easily the electrons in the molecules can ___ (ie. be ___). ____ molecules in which the electrons are ___ from the nucleus are easy to polarize,

Answer 32

move, polarized, large, nucleus

Question 33

LDFs are responsible for the gaseous phase of ___ __ at any temperature, since no other __ __ exist between the atoms of noble gases. the ___ __ at which noble gasses liquify is to some extent indicative of the ___ of dispersion forces between the atoms

Answer 33

noble gasses, intermolecular forces, low temperature, magnitude