Chapter 9

Question 1

What are degenerate orbitals?

Answer 1

orbitals that have same energy. Think of how p has 3 different orbitals in same energy

Question 2

Aufbau’s Principle

Answer 2

fill up lower energy levels with electrons first

Question 3

Hund’s rule

Answer 3

When adding electrons in degenerate orbitals, add electrons one at a time with parallel spins

Question 4

What are the main group elements?

Answer 4

Elements in group 1, group 2, and groups 13-18

Question 5

What are valence electrons?

Answer 5

electrons most important in chemical bonding

Question 6

Where are valence electrons for main group elements?

Answer 6

Valence electrons are those in the outermost principal energy level

Question 7

Where are the transition elements on the periodic table?

Answer 7

Elements found in groups 3-12

Starts with Sc, ends with Zn

Question 8

What is different about valence electrons for transition elements?

Answer 8

The outermost d electrons are counted as valence with the outermost principal energy level electrons

Question 9

chemical properties of an element depend on what?

Answer 9

Its valence electrons, they are held most loosely so they are the easiest to loose/share

Question 10

Why do elements in a column of the periodic table have similar chemical properities?

Answer 10

They have the same number of valence electrons

Question 11

The other electrons in an atom (other than valence) are called what?

Answer 11

core electrons

Question 12

Where is the s-block on the periodic table?

Answer 12

First two columns on the left side with Helium (HE) on the right

Question 13

Where is the p block on the periodic table?

Answer 13

First six columns on the right excluding He, made up of halogens and nobel gases

Question 14

Where is the d block on the periodic table?

Answer 14

starts after s block elements on the left (3rd column) to 12th column on right before p block elements

Question 15

Where are the f-block elements?

Answer 15

2 rows at the bottom

Question 16

number of columns in a block corresponds to the maximum what?

Answer 16

number of electrons that can occupy the particular sublevel of that block

ex: s block has two columns bc 1 s orbital can hold two electrons

p block has 6 columns bc 3 p orbitals with 2 electrons each

d block has 10 columns corresponding to 5 d orbitsld with two electrons each

Question 17

the number of valence electrons in main-group element is equal to

Answer 17

its lettered group number

ex: chlorine has 7 valence electrons because its in group 7A

Question 18

the row number in the periodic table is equal to

Answer 18

the highest occupied principal level

ex: chlorine in row 3, highest principal level is n=3 level

Question 19

van der Waals radius

Answer 19

atomic radius determined by the distance between nonbonding atoms in direct contact

Question 20

What is bonding atomic radius or covalent radius?

Answer 20

nonmetals: 1/2 the distance between two atoms bonded together
metals: 1/2 the distance between two of the atoms next to eachother in a crystal or metal

Question 21

what is atomic radius?

Answer 21

set of average bonding radii determines from measurements on a large number of elements or compounds

Question 22

How are atomic radius and van der Wall radius different?

Answer 22

atomic radius represents the radius on an atom when it is bonded to another atom and is always smaller than van der Waal

Question 23

What is the bond length of two covalently bonded atoms?

Answer 23

sum of their atomic radii

Question 24

What are the two general trends on periodic table for van der Waals radii?

Answer 24

1. As we move down a column in periodic table, atomic radius increases
2. As we move to the right across a period (row) atomic radius decreases

Question 25

The atomic radius decreasing as you go to the right is caused by what?

Answer 25

inward pull of electrons in outermost principal energy level

Question 26

what is the effective nuclear charge?

Answer 26

the average or net charge experienced by an electron

Question 27

What is equation for effective nuclear charge?

Answer 27

Z_eff = Z (actual nuclear charge)-S (charge screened by other electrons)

Question 28

What is shielding?

Answer 28

Repulsive force exerted on valence electrons by core electrons

Question 29

what increases the shielding effect?

Answer 29

more core electrons

Question 30

What are some effects of the shielding effect?

Answer 30

atomic radius increases (electrons pushed out), Ionization energy decreases (electrons are easier to add/drop when further away), and electronegativity decreases (electrons aren’t as close to nucleus)

Question 31

How to find greatest shielding energy?

Answer 31

elements with the most electrons

Question 32

What are the two different types of shielding?

Answer 32

-shielding of the outermost electrons by the core electrons and shielding of the outermost electrons by eachother

Question 33

core electrons shield electrons in outermost principal energy level from what?

Answer 33

nuclear charge. Outermost electrons don’t shield eachother from nuclear charge

Question 34

What is the different trend for transition elements?

Answer 34

they stay roughly constant across each row, because the number of electrons in the outermost principal energy level is nearlt constant

Question 35

What is penetration?

Answer 35

Ability of an electron in a given subshell to penetrate within other shells and get close to the nucleus

Question 36

What does this graph show?

Answer 36

Radial probabilty function

-shows penetration in individual orbitals

Question 37

paramagnetic vs diamagnetic

Answer 37

paramegnetic have unpaired electrons, diamagnetic only have paired electrons