Electron Configuration

Multiple Choice

How many electrons does Si contain? (click to see image)

• 14

• 28

• 2

• 4

Multiple Choice

How many electrons can the first energy level hold?

• 1

• 2

• 8

• 0

Multiple Choice

How many electrons can you put in the 2nd Energy Level?

• 2

• 6

• 8

• 18

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

Multiple Choice

True or False: the electron cloud has a clear, distinct boundary

• true

• false

• n = How far away from the nucleus an electron is on average

• Are a whole number value greater​ than 1

  • The larger the number, the farther away from the nucleus an electron is

  • In our periodic tables, the highest n value we know to exist is 7

• Electrons with the same n value are all in the same shell

​Principle Quantum number: n

Multiple Choice

How many energy levels are on the periodic table?

• 3

• 18

• 5

• 7

The Shell Model

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

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

    • s, p, d, f

Experience Chemistry | Lesson 1.4

The Shell Model

• 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

Multiple Choice

An orbital diagram uses arrows to represent...

• electron cloud

• protons

• shells

• electrons

Multiple Choice

How many electrons can each orbital (box) hold?

• 2

• 6

• 7

• 14

Multiple Choice

Which element is pictured?

• neon

• fluorine

• magnesium

• argon

Multiple Choice

The 4 orbitals are

• s, p, d, f

• a, b, c, d

• 2, 4, 6, 8

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

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

  • S orbitals can hold 2 electrons

Experience Chemistry | Lesson 1.4

Atomic Orbitals

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

  • Dumb bell shaped, with 3 orbitals

  • holds 6 total electrons

  • Can face different directions

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

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Every shell from the third level up has a d-orbital

  • 5 orbitals holding 10 total electrons

Experience Chemistry | Lesson 1.4

Multiple Choice

How many d orbitals are there in a given sublevel?

• 1

• 3

• 5

• 7

Atomic Orbitals

• Every shell from the fourth level up has a f-orbital

  • 7 orbitals holding 14 total electrons

  • Have a shape too complex to show as a picture

Experience Chemistry | Lesson 1.4

Match

Match the sub shell shape to its name

S

p

d

• S

• p

• d

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

Pauli Exclusion Principle

No two electrons in the same atom can have identical values for all four of their quantum numbers.

In other words:

(1) no more than two electrons can occupy the same orbital

(2) two electrons in the same orbital must have opposite spins 

Aufbau Principle

states that electrons fill lower-energy atomic orbitals before filling higher-energy ones (Aufbau is German for "building-up")

Hunds Rule

every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.

Multiple Choice

Electrons occupy orbitals of lowest energy first is part of what electron configuration rule?

• Hund’s Rule

• Aufbau Principle

• Pauli Exclusion Principle

How to Write an Electron Configuration:

1. Start with the shell/period number

2. Followed by the type of orbital

3. Finally the superscript indicates the number of electrons in the orbital

Example: B = 1s² 2s² 2p¹

Each shell (n) has that number of subshells in it.

Shell 1 = 1 sublevel (s)

Shell 2 = 2 sublevels (s & p)

Shell 3 = 3 sublevels (s, p, & d)

Shell 4 = 4 sublevels (s, p, d, & f), etc.

​

How to Write an Electron Configuration:

This picture shows the trick of the order to write the orbitals.

If we wrote all these it would say:

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴ 6d¹⁰ 7p⁶ 8s²

Multiple Choice

What do you start all electron configurations with?

• 1s

• 1d¹⁰

• 1f¹⁴

• 1p⁶

Electrons

If you add the exponents, you get the total number of electrons. This one would have 120 electrons

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴ 6d¹⁰ 7p⁶ 8s²

Multiple Choice

What atom matches this electron configuration?
1s²2s²2p⁶3s²3p⁶4s²3d¹⁰

• Zinc

• Copper

• Nickel

• Germanium

Multiple Choice

What atom matches this electron configuration?
1s²2s²2p⁶3s²

• Neon

• Magnesium

• Aluminum

• Potassium

Multiple Choice

What electron configuration matches an oxygen atom?

• 1s²2s²2p⁶3s2, 3p⁶4s²3d¹⁰4p⁵

• 1s²2s²2p⁴

• 1s²2s²2p⁶

• 1s²2s²2p⁶3s²3p⁶4s²3d¹

Multiple Choice

Which electron configuration belongs to Chlorine (Cl)?

• 1s² 2s² 2p⁶ 3s² 3p⁵

• 1s² 2s² 2p⁶ 3s² 3p⁶

• 1s² 2s² 2p⁶ 3s² 3p⁷

Multiple Choice

How many p orbitals are there in a sublevel?

• 2

• 1

• 4

• 3

Multiple Choice

How many electrons can the d sublevel hold?

• 8

• 10

• 2

• 4

Multiple Choice

What atom matches this electron configuration?
[Xe] 6s² 4f¹⁴ 5d⁹

• Mercury

• Gold

• Platinum

• Thallium

Multiple Choice

Each row on the periodic table represents:

• an energy level

• a sublevel

• an electron

• an orbital