bell work what is the electron configuration for an element with atomic number 47? if you missed...

Bell Work

• What is the electron configuration for an element with atomic number 47?

• If you missed yesterday – What group are the following elements in?

• Li, K, P, N, Ne, Al, Be, and Br

Physical Science – Lecture 36

Valence Electrons

Remember:Each s gets 2 electrons.Each p gets 6 electrons.Each d gets 10 electrons.Each f gets 14 electrons.Add up the total number of subscripts to determine how many electrons you have.

Electron Orbits

• For each orbit around the nucleus, there can be a certain number of electrons in the total orbit.

• Remember when we said 2 could be in the first shell and 8 for the 2nd and 3rd shells for the first 18 elements?

Use of the Electron Configuration

• The electron configuration can tell you the total number of electrons in an element and the total number of electrons in each shell.

Finding the number of Electrons in each shell

• To find the number of electrons in each shell, follow these steps.

• Step 1: Write the electron configuration for that element.

• Step 2: Count the total number of electrons (superscripts) in each shell with the same large number in front.

Example

• 1s22s22p63s23p64s23d10

Example

• 1s22s22p63s23p64s23d10

• The first big number is 1. • There is only one sub-shell with the number

one. There are two electrons in that subshell.• Therefore, there are two electrons in the first

shell.

Example

• 1s22s22p63s23p64s23d10

• The second big number is 2. • There are two sub-shells with the number two.

There are two electrons in the first subshell and 6 electrons in the second subshell.

• Therefore, there are 8 electrons in the second shell.

Example

• 1s22s22p63s23p64s23d10

• The third big number is 3. • There are three sub-shells with the number

three. There are two electrons in the first subshell, 6 electrons in the second subshell, and ten electrons in the third subshell.

• Therefore, there are 18 electrons in the third shell.

Example

• 1s22s22p63s23p64s23d10

• The fourth big number is 4. • There is one sub-shell with the number four.

There are two electrons in that subshell.• Therefore, there are only 2 electrons in the

fourth shell.

What does that look like?

• 2 electrons in the first shell, 8 in the second shell, 18 in the third shell, and 2 in the last shell.

How is this helpful?

• The number of electrons in the outer energy level corresponds to the number of valence electrons for that element.

Valence Electrons

• Equal to the group number• Represents electrons in the outer energy level• Elements want valence electrons equal to

noble gases (group 8A)

Valence Electrons

• 1A = 1 valence electron• 2A = 2 valence electrons• 3A = 3 valence electrons• 4A = 4 valence electrons• 5A = 5 valence electrons• 6A = 6 valence electrons• 7A = 7 valence electrons• 8A = 8 valence electrons

Electron Dot Structures

• Indicates the number of electrons surrounding an element in the outer energy level.

• Represents valence shell electrons

Electron Dot Structure Chart(1A) (2A) (3A) (4A) (5A) (6A) (7A) (8A)

Chlorine

• What column is chlorine in?

• What is the group number?

• How many valence electrons does Chlorine have?

Phosphorus

• What column is phosphorus in?


• How many valence electrons does phosphorus have?

Oxygen

• What column is oxygen in?


• How many valence electrons does oxygen have?

Beryllium

• What column is beryllium in?


• How many valence electrons does beryllium have?

Neon

• What column is neon in?


• How many valence electrons does neon have?

Potassium

• What column is potassium in?


• How many valence electrons does potassium have?

Lithium

• What column is lithium in?


• How many valence electrons does lithium have?

Electron Dot Structure

Li

Bromine

• What column is bromine in?


• How many valence electrons does bromine have?

Electron Dot Structure

Br

GAME TIME!

• Winning Team gets a 100, second place gets a 90, third place gets 80.

• Non-participants get a 60.

Directions

• For each slide, first draw the correct elemental symbol for the given name of the element;

• Then, clearly draw the correct number of electrons around the symbol.

• If I cannot see the electrons, they do not count.

• Then, write the number of valence electrons out to the side of the elemental symbol.

Nitrogen

Helium

Oxygen

Hydrogen

Potassium

Magnesium

Aluminum

Krypton

Sodium

Chlorine

Sulfur

Silicon