Bonding and Chemical Interactions (3)

Question 1

Electronic geometry

Answer 1

describes the spatial arrangement of all pairs of electrons around the central atom, including both the bonding and the lone pairs.

(CH4 , NH3 and H2O all have tetrahedral electronic geometry but differ in their molecular shapes.)

Question 2

Molecular geometry

Answer 2

describes the spatial arrangement of only the bonding pairs of electrons.

(CH4 is tetrahedral , NH3 is pyramidal and H2O is bent)

Question 3

Cation

Answer 3

atoms that lose the electrons

meTals lose electrons to become caTions = + charge

Question 4

Anion

Answer 4

atoms that gain electrons

(Nonmetals gain electrons to become aNions = Negative (-) charge ).

Question 5

Formal charge

Answer 5

Valence electrons - bonds - lines

Question 6

Sigma bonds

Answer 6

result of head to head overlap.

Bond allow for free rotation

Question 7

Pi bonds

Answer 7

result of the overlap of two parallel electron cloud densities.
Do not allow free rotation because the electron densities of the orbitals are parallel and cannot be twisted.

Question 8

Periods

Answer 8

rows

Question 9

Families

Answer 9

column

Question 10

Effective nuclear charge (Zeff)

Answer 10

a measure of the net positive charge experienced by the outermost electrons

increases left to right
up and right

Question 11

Atomic and Ionic Radii

Answer 11

refers to the size of a neutral element, while an ionic radius is dependent on how the element ionizes based on its element type and group number

Increases right to left
down and left

Question 12

Ionization energy (IE)

Answer 12

the energy required to remove an electron from gaseous species.

Removing electrons from an atom requires the input of heat, which makes it an endothermic processes.

Mg –> Mg+ + e- first ionization energy

Mg+ –> Mg2+ + e- second ionization energy

Question 13

Electron affinity

Answer 13

refers to the energy dissipated by gaseous species when it gains energy. Exothermic process

Question 14

BEAR (Mneomnic)

Answer 14

B (basicity) E(electonegativity, EA
and IE)

A(acidity) R (radius)

Question 15

Incomplete octet

Answer 15

elements are stable with fewer than 8 electrons in their valence shell:
Hydrogen (2)
Helium (2)
Lithium (2)
Beryllium (4)
Boron (6)

Question 16

Expanded octet

Answer 16

any elements in period 3 and greater can hold more than 8 electrons including:
Phosphorus (10)
Sulfur (12)
Chlorine (14)

Question 17

Bond order

Answer 17

As bond order increases, bond strength increases, bond energy increases, bond length decreases

triple bond –> bond strength ↑ , bond energy ↑ , bond length ↓

Question 18

Bond energy

Answer 18

the energy required to break a bond by separating its components into their isolated, gaseous atomic states.

Question 19

Range of electronegativies

Answer 19

nonpolar bonds –> 0 to 0.5

polar bonds –> 0.5 to 1.7

ionic bonds –> higher than 1.7

Question 20

Dipole moment Equation

Answer 20

p = qd

q= charge
d= distance

Question 21

VESPER Theory (molecular geometry)

only bonding electron pairs aka bonds

Answer 21

2 ——–> Linear
3 ———> Triagonal planar Bent
4 ———> Tetrahedral Trigonal pyramidal, Bent
5———->Trigonal Bipyramidal Seesaw, T-shaped, Linear
6———-> Octahedral Square pyramidal, square
planar, T-shaped, Linear

Question 22

Electronic geometry vs Molecular geometry

Answer 22

CH4, NH3, and H2O all have tetrahedral molecular geometry but differ in their molecular shapes.

CH4 is tetrahedral, NH3 is trigonal pyramidal, H2O is bent as molecular shape.

Question 23

London dispersion force (van der Waals force)

Answer 23

weakest interactions but are present in all atoms and molecules.

Size ↑ , London dispersion force ↑

Question 24

Dipole-Dipole interaction

Answer 24

occurs between oppositely charged ends of polar molecules, stronger than London forces. Present in solid and liquid phases but no in the gas phase.

Question 25

Hydrogen bonding

Occurs in FON (phone)

Answer 25

the strong form of dipole-dipole interaction. Strongest intramolecular force and intermolecular.

FON (phone)
Fluorine
Oxygen
Nitrogen