Exam 2 Chapter 7

Question 1

Electron configuration:

Answer 1

the order of filling of orbitals;

tells us which orbitals are filled or partially filled

Question 2

Core electrons

Answer 2

those in filled shells

“inner shell electrons”

Question 3

Valence electrons:

Answer 3

those beyond the filled shells

“outer shell electrons”

Question 4

Effective nuclear charge formula

Answer 4

Z_eff = Z - S

Question 5

How far are the electrons from the nucleus for three Noble gases (He, Ne, Ar)?

Answer 5

Question 6

What is responsible for the differences in orbital sizes for different atoms

Answer 6

Electrostatic interactions

Question 7

electrostatic repulsion

Answer 7

particles with like charges repel one another

Question 8

•particles with opposite charges are attracted to each other

Answer 8

electrostatic attraction

Question 9

What is directly related to the relative magnitudes of the charges on the particles?

Answer 9

The stren gth of an electrostatic attraction

Question 10

is inversely related to the distance between the interacting particles

Answer 10

The strength of an electrostatic attraction

Question 11

The potential energy of two interacting charged particles (formula)

Answer 11

E=potential energy of two interacting charged particles

Q=magnitude of charge

d=distance

Question 12

What is responsible for the differences in orbital sizes for different atoms differences in orbital si zes for different atoms?

Answer 12

Electrostatic interactions

Question 13

The concepts of nuclear charge, inner electron shielding and electrostatic attraction/repulsion are important in predicting what three important chemical proerties of atoms:

Answer 13

Atomic Size

Ionization energy

Electron affinity

Question 14

Assumptions of the onion peel model

Answer 14

Question 15

What is this really representing?

Answer 15

Question 16

What is the border of an attom

Answer 16

It’s a probability boundary

Question 17

What are the two ways to measrue radius of an atom?

Answer 17

Question 18

How do you measure a Van der Waals radius?

Answer 18

Take the distance between 2 of the same non-touching atoms and divide by two

or subtract a known radius of one atom from the total distance

Question 19

How do you mearsure a Covalent radius?

Answer 19

Take the distance between 2 covalently bonded atoms and divide by two

or subtract a known radius of one atom from the total distance

Question 20

Why do atomic radii decrease as the period is read from left to right?

Answer 20

The Z_eff on the valence electrons gets higher, so
the positive energy from the nucleus holds valence electrons closer.

Question 21

When does atomic radii increase?

Answer 21

when moving right to left in a period

when moving top to bottom in a group

Question 22

When does atomic radii decrease?

Answer 22

when moving left to right in a period

when moving bottom to top in a group

Question 23

Why does atomic radii increase as groups are read from top to bottom?

Answer 23

There are more electrons from other energy shells taking up space.

Question 24

Sodium is bigger than lithium because…

Answer 24

it has more electrons

Question 25

Ionization energy:

Answer 25

The minimum energy required to remove an electron from the ground state of the isolated gaseous atom

Question 26

In context of ionizing energy: What is reported with units of kJ/mol

Answer 26

it is the energy required to remove one mol of electrons from one mol of gaseous atoms

Question 27

What happens to the **Energy required to remove e-** as we move from I_n to I_n+!?

Answer 27

It doubles

Question 28

What happens to the **Energy required to remove e-** as we move from I_n to I_n-1?

Answer 28

it halves

Question 29

What happens to **Z_eff felt by departin electron** when photons begin ionizing electrons from new valence shells?

Answer 29

The new valence electrons no longer act as shields, so they are no longer subntracted from the atomic number to get Z_eff

Question 30

As atomic radius gets bigger,

Answer 30

ionizing energy gets smaller

Question 31

As atomic radius gets smaller,

Answer 31

ionizing energy gets larger

Question 32

As Z_eff increases,

Answer 32

ionizing energy increases

Question 33

What happens when Z_eff moves down the group?

Answer 33

it stays constant

Question 34

Where do irrecularities in first ionization energy trends appear?

Answer 34

2A--\>3A 5A--\>6A

Question 35

What explains the irregularity in ionizing energy between 2A and 3A?

Answer 35

Orbitals of lower energy are shielding orbitals of higher energy

Question 36

What explains the irregularity of electron ionization energy between 5A and 6A?

Answer 36

Electrons are slightly more resistent to being pulled out of a spin party

Question 38

Define Electron affinity (EA)

Answer 38

The energy change associated with the addition of an electron to a gaseous atom or ion

Question 39

What happens when E.A. is negative (-) E.A.

Answer 39

Question 40

What happens when E.A. is positive (+) E.A.

Answer 40

Question 41

What is the energy change associated with adding **one mol of electrons to one mol of gaseous atoms** or ions?

Answer 41

1KJ/mol

Question 42

What are the trends for Electron affinity?

Answer 42

More negative as periods move from left to right No correlation as moving through the groups.

Question 43

Why are the Electron Affiniy values for 2A positive or small negative?

Answer 43

a new electron would be added to an orbital of a higher energy. Therefore, *new electrons would be **shaded*** from *effective nuclear attraction*. **Z_eff=atomic number-shading electrons** **Z_{eff(2A+elec)=}**atomic number-atomic number

Question 44

Why are the Electron Affiniy values for 5A positive or "out of pattern"?

Answer 44

It takes extra energy to add an electron that doesn't fit in with the **dogma of the spin party.**

Question 45

Why are the Electron Affiniy values for Noble Gasses Positive?

Answer 45

They are very effectively shaded

Question 46

Why doesn't the Electron Affinity value correlate to period number?

Answer 46

Counteracting effects: Being close to the atom ***increases electrostatic attraction*** _to the nucleus_ Being close to the atom ***increases electrostatic repulsion*** _to other electrons_ (not enough space)