SS Chem Unit 4 Lesson

Electron Configuration

Mrs. Nebzydoski's Lesson

Revising the Atomic Model

• Atomic Orbital: an area around the nucleus where there is a high probability of finding an electron

  • Boundaries are not clear and distinct, but fuzzy

Experience Chemistry | Lesson 1.4

The Shell Model

• The shell model of the atom is a simplified version of the quantum mechanical model

  • Described with four quantum numbers

    • Each shell has one or more sub-shells inside of it (l)

      • s, p, d, f

    • Each sub-shell holds at least one orbital that holds 2 electrons each

      • s= 1 orbital, 2 electrons

      • p=3 orbitals, 6 electrons

      • d= 5 orbitals, 10 electrons

      • f=7 orbitals, 14 electrons

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

  • Every shell has one s-orbital, which has a spherical shape

  • The probability of finding an electron does not depend on the direction the orbital is rotated

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

  • Every shell on the second energy level upwards has three p-orbitals

    • Dumb bell shaped, with 3 orbitals

      • Can face different directions

    • Electrons are found anywhere in the shape itself, but not outside of them

Experience Chemistry | Lesson 1.4

Multiple Choice

There are _____ types of atomic orbitals.

• 1

• 2

• 3

• 4

Electron Configuration tells you the location that an electron "lives" at in an atom

• There are four types of orbital shapes

• S, p, d, & f

Match

Match the sub shell shape to its name

S

p

d

• S

• p

• d

Each orbital can contain up to 2 electrons

• s orbitals can hold a total of 2 electrons (1 orbital)

• p orbitals can hold a total of 6 electrons (3 orbitals)

• d orbitals can hold a total of 10 electrons (5 orbitals)

• f orbitals can hold a total of 14 electrons (7 orbitals)

Periodic Table and Orbitals

The periodic table gets its shape from the type of atomic orbitals that are filled in the atoms of the collumns.

Match

Match the number of electrons each sub shell can hold to the sub shell name

• 2

• 6

• 10

• 14

S

p

d

f

• S

• p

• d

• f

The blocks of the periodic table

As you can see here the "s" block is shown on the left in pink, the "p" block is on the right in orange, the "d" block is in the middle shown in blue, and the "f" block is shown below in yellow.

Multiple Choice

Look at a periodic table. Count how many columns on the periodic table are in the "p" block. How many columns did you find?

• 2

• 6

• 10

• 14

Columns on the periodic table and the orbitals...

• The s block contains 2 columns

• The p block contains 6 columns

• The d block contains 10 columns

• The f block contains 14 columns

Think about it....

The s block contains 2 columns and the "s" orbitals can contain 2 electrons. The p block contains 6 columns and the "p" orbitals can contain up to 6 electrons. The d block contains 10 columns and the the "d" orbitals can contain up to 10 electrons! (This is NOT a coincidence!)

Orbital filling

Electrons fill these orbitals in a way that allows them to take the easiest root possible. The LOWEST energy levels are filled first.

Multiple Choice

Forces that holds atoms together within the molecule

• intermolecular forces

• intramolecular forces

Multiple Choice

Intermolecular Forces are the forces that exist

• Between two or more molecules

• Within a single molecule

• Only in molecules containing carbon

• In all molecules

Multiple Choice

Which of the following factors plays an important role in the identification of specific intermolecular forces in a molecule?

• bond type

• density

• solubility

• molecular polarity

Multiple Choice

The intermolecular force present in all matter is

• Hydrogen Bonding

• Ionic Bonding

• Dipole-Dipole

• London or Dispersion

Multiple Choice

The strongest IMF is

• London/Dispersion

• Dipole-Dipole

• Hydrogen Bonding

Multiple Choice

For hydrogen bonding to occur, a molecule must have a hydrogen bonded to

• carbon

• another hydrogen

• Fluorine, Chlorine or Oxygen

• Fluorine, Nitrogen or Oxygen

Multiple Choice

The weaker the intermolecular forces of a substance the _____________ the boiling point

• higher

• lower

Multiple Choice

In general, substances with stronger intermolecular forces have ________ boiling points than those with weaker forces

• Higher

• Lower

• The same

Multiple Choice

Which of the following is NOT a type of intramolecular force?

• Covalent bonding

• Hydrogen bonding

• Ionic bonding

• Metallic bonding

Molecular Shapes

Lesson 4

VSEPR Model

• The molecular geometry

(shape) of a molecule can be
determined using the Valence
Shell Electron Pair Repulsion
model, or VSEPR model.

• It is based on an arrangement

that minimizes the repulsion of
shared and unshared electron
pairs around the central atom.

Multiple Choice

 A lone pair is defined as

• A pair of bonding electrons

• One non-bonding electron

• A pair of non-bonding electrons

• A pair of electrons on the central atom

Multiple Choice

The model is based on the principle that electron pairs around the central atom ------ each other.

• bond

• attract

• repel

Multiple Choice

The ------ of the molecule determines the properties of the compounds.

• density

• shape

• mass

• The Lewis structure of carbon tetrachloride provides information about connectivities, provides information about valence orbitals, and provides information about bond character.

Multiple Choice

How many lone pair does each Chlorine atom have around it?

• 6

• 2

• 8

• 3

Tetrahedral

However, the Lewis structure provides no information about the shape of the molecule, which is defined by the bond angles. For carbon tetrachloride, each C-Cl bond angle is 109.5°. Hence, carbon tetrachloride is tetrahedral in structure:

Tetrahedral

Therefore, if the central atom has 4 things bonded to it and NO lone pairs (like CH₄)(or CCl₄) then the shape will be tetrahedral with bond angles of 109.5^⁰

Linear

If the central atom has two bonded pair (bonded with two other atoms) and no lone pairs that is called linear

Multiple Choice

A linear molecule has _______ bonded pairs and _______ lone pairs on the central atom.

• 2, 0

• 0, 2

• 2, 2

• 0, 0

Linear

Linear molecules have a bond angle of 180^⁰, meaning there is that much space between each set of electrons

Trigonal Planar

Trigonal Planar molecules have three bonded pair and no lone pair on the central atom

Trigonal Planar

An example of trigonal planar is boron trifluoride, BF₃. There are three things bonded to the central atom and the central atom has no lone pairs. The bond angle is 120⁰

Bent

Molecules with two bonding pair and two lone pair are called bent. H₂O is the classic example of a bent molecule. There are two hydrogens connected to the central atom, oxygen, and the central atom has 2 lone pair.

Multiple Choice

A bent molecule has _______ lone pair and _______ bonded pair.

• 2, 2

• 0, 0

• 2, 0

• 0, 2

Multiple Choice

What shape is this?

• Bent

• Linear

• Tetrahedral

• Trigonal Planar

Multiple Choice

What molecular shape is this?

• Bent

• Linear

• Tetrahedral

• Trigonal Planar

Multiple Choice

What molecular shape is this?

• Bent

• Linear

• Tetrahedral

• Trigonal Planar

Drag and Drop

A ​

Placeholder

is a positively charged metal ion. It is positive because metals ​

Placeholder

electrons when they form ionic bonds.

Drag these tiles and drop them in the correct blank above

cation

lose

anion

gain

Multiple Select

Select the compounds that are covalent

• NBr₃

• Al₂O₃

• CH₄

• PCl₅

• FeO

B. Ionic Names

1. Write the names of both elements, cation first. (the metal is the cation)

2. Change the anion’s (nonmetals) ending to -ide.

3. For ions with variable oxidation #’s, write the ox. # in parentheses using Roman numerals. Overall charge = 0.

Multiple Choice

What are oxidation numbers?

• Number of electrons in the outer most energy level

• Number of protons

• Electrons gained or lost in chemical bonding

• Number of neutrons gained or lost

Multiple Choice

For any neutral compound, the sum of the oxidation numbers of the atoms in the compound must equal ..........

• -1

• +2

• 0

Multiple Choice

Select the correct name for KBr?

K = potassium, Br = bromine

• potassium bromine

• potassium monobromine

• phosphorus bromide

• potassium bromide

Multiple Choice

Select the correct name for SrCl₂?

Sr = Strontium, Cl = chlorine

• strontium dichloride

• strontium chloride

• strontium chlorine

• strontium carbon diioidide

Multiple Choice

What is the correct name for P₂Cl₄?

P = phosphorus, Cl = chlorine

• Phosphorus chloride

• phosphorus tetrachloride

• phosphorus chlorine

• diphosphorus tetrachloride

Multiple Choice

What is the name for As₄O₁₀?

As = arsenic, O = oxygen

• Tetraarsenic decaoxide

• arsenic oxide

• tetraarsenic tenoxide

• tetraarsenic decaoxygen