Atomic structure and interatomic bonding Chpt 2

Question 1

What is the net force

Answer 1

sum of attractive and repulsive forces

Question 2

What do the attractive force depend on

Answer 2

depends on type if bonding that exists

Question 3

What causes repulsive forces?

Answer 3

when negatively charged electron clouds interact with small distances and when outer electron shells overlap

Question 4

When does further pushing or pulling from atoms prevented by attractive and repulsive forces

Answer 4

.3nm

Question 5

What are the primary and secondary bonding forces

Answer 5

ionic, covalent and metallic

van der waals

Question 6

What subatomic particle has a smaller massq

Answer 6

electorn

Question 7

Where is the atomic number located?
atomic mass?

Answer 7

bottom left
top left

Question 8

Explain carbon-15

Answer 8

number of carbon is 12 but has 3 neutrons

Question 9

Unit for atmoic mass. how is it defined

Answer 9

amu

1/12 of atomic mass of most common isotope carbon atom (6protons 6 neutrons

Question 10

Whatis the z number?

Answer 10

protons

Question 11

Whats bhors atomic model

Answer 11

think rings n=3 etc

electrons in orbitals

Question 12

What is the wave-mechanical model?QAs`

Answer 12

tells us that electrons move in fuzzy orbits, not circular

Can only tell you probability of finding them at various locations around the nucleus

electrons considered to have wave and particle like characteristics

Question 13

What is the Quantum-mechanical principle

Answer 13

Energies of electrons are quantized

principles that govern sys of atomic and subatomic entities

Question 14

What are subatomic particle charges measured in

Answer 14

Coulombs

attractive bonding forces are coulombic

Question 15

Charge of pr and el

Answer 15

1.602 x 10^-19C

Question 15

What letter is the atomic number

Answer 15

Z

Question 16

Atomic mass vs atomic mass unit vs atomic weight

Answer 16

atomic mass: neutrons v protons

1/12 of atomic mass of most common carbon isotope carbon-12

average weight of the atom’s isotopes

Question 16

What letter is atomic mass

Answer 16

A

Question 16

mole is?

Answer 16

6.022 x 10^23

Question 17

1amu/atom(or molecule) = 1g/mole

Question 17

Can electrons have different energies?

Answer 17

YES! they can change energy orbitals and have different energies in different moments

Question 17

Pauli exclusion principle

Answer 17

No two electons in same atom have identical values for all four of their quantum numbers

Question 18

electron configuration

Question 19

Describe all four quantum numbers

Answer 19

Principle Quantum Number (n): tells you the energy level of an electron inside an atom (size of electron orbital)

Angular Momentum Quantum Number (l): describes the shape of the sublevel within an energy level
s (shere) - 0 has one orbital
p (3D infinity) - 1 has 3 orbitals
d (4 flat bubbles) - 2 has 5 orbitals
f (two bubles as axis) - 3 has 7 orbitals

Magnetic Quantum Number (m_l): describes orbital within sublevel
-l <= m_l <= l

Electron Spin (m_s): can be +1/2 or -1/2
an electron in an orbital can either go up or
down
ex: 3d^8 is a -1/2 or +1/2 depending on if
you start with all down or up arrows

https://www.youtube.com/watch?v=eRIN9CPDrpo

Question 20

Whats ground state

Answer 20

the lowest energy an atom can be in

Question 21

Are noble gases reactive or unreactive

Answer 21

unreactive

Question 22

name the column names

Answer 22

8th: noble (inert) gases 7th: halogens 4-6: other nonmetals (including hydrogen) 3rd: metalliods ( horizontal pattern) between 2 and 3: transition metals 2nd: alkaline earth metals 1st: alkali metals study periodic table upper low: lanthanides lower low: actinides

Question 23

describe the periodic table trend with spdf

Question 24

Electropositive vs electronegative and periodic trend

Answer 24

+: willing to give up electron -: readily accept electrons more electronegative as you move to the right of P.T.

Question 25

Ionic vs covalent bonding

Answer 25

metal and nonmetal bonding (transferring electrons requires large electronegative difference nondirectional bond. dissolve in water easily and other polar solvents. Tend to form crystalline solids with high melting temperature between atoms of small electronegative differences (near in periodic table). orbital overlap. Highly directional bonding bc they bond in the direction of greatest orbital overlap (diamonds, polymeric molecules like ethylene, ceramics and semi-conductors)

Question 26

Where do electrons go when they have more energy?

Answer 26

higher orbital

Question 27

What does the group number tell you about an atom

Answer 27

the number of electrons available

Question 28

when atoms are at r0?

Answer 28

atom is in equillibrium

Question 29

Whats bonding energy E_o?

Answer 29

amount of energy required to break a mole of molecules into component atoms

Question 30

Equilibrium is reached in forces when bonding energy is minimized

Question 31

cation vs anion

Answer 31

cation (+) anion (-)

Question 32

What are nondirectional bonds

Answer 32

when the direction of the attraction between atoms do not matter.

Question 33

Why do electrons transrer in ionic bonding?

Answer 33

atoms want to be at a ground state level, meaning they want to reduce the energy of the system.

Question 34

how do you name an ionic compound

Answer 34

name the metal first, then the nonmetal second

Question 35

What is mtallic Bonding?

Answer 35

valence electrons detached from atoms and swim in electron sea that glues ions together. Non-directional bonding metal is held together by strong force of attraction between positive nuclei and delocalized electrons

Question 36

What is non-directional bonding

Answer 36

probability of sharing electron is equal in all directions

Question 37

What happens to nuclei when valence elctron are in elecytorn sea?

Answer 37

nucleus and core electrons for ion cores with net positive charge,

Question 38

what are delocalized electrons

Answer 38

valence electrons that don't belong to any one atom.

Question 39

What is the van de Waals

Answer 39

weak attractive force between dipoles like when sodium chloride positive side attracts negative other atom secondary attractive

Question 40

what are dipoles

Answer 40

pair of electric charges or magnetic poles of equal but opposite charge, separated by small distance

Question 41

Whats permanent dipole?

Answer 41

like when sodium chloride positive side attracts negative other atom all due to asymmetrical arrangment of positive and negative regions strongest secondary bond

Question 42

How do polar molecules affect nonpolar molecules?

Answer 42

makes them polar, lol bond is formed due to attraction between permanent and induced dipoles

Question 43

can electrically symmetric molecules and atoms create a dipole

Answer 43

yes. fluctiations in electron density (fluctuating dipoles) weakest bond

Question 44

what bonding in each material? metals ceramics polymers semiconductors

Answer 44

metallic ionic/covalent covalent and secondary covalent or covalent/ionic

Question 45

periodic trend for atomic size, electronegativity, ionization

Question 46

calculate the ionic percentage of materials

Answer 46

IC% = {1-exp(-(0.25)(X_A-X_B)^2)}*100 X_A and X_B are the electronegativity of the elements in the materials

Question 47

table for bonding energies and melting temperatures

Question 48

look at last slide of week 3