Electron Configuration and Periodic Trends Lesson

By Andrew Nelson

Periodic Trends

Objectives

• Label trends in the table

• ​Explain why the trends exist

• ​Explain the difference between cations and anions

​Some text here about the topic of discussion.

Refresh: What is the electron configuration of Neon

Multiple Choice

Knowing this electron configuration of neon, how many valence electrons would it have?

• 2

• 4

• 6

• 8

Multiple Choice

Which group is the following element found in: [Ar] 4s²

• 1

• 2

• 14

• 5

Multiple Choice

Which Period is the following element found in: [Ar] 4s²

• 1

• 2

• 4

• 5

Why does the left side have a larger radius?

Multiple Choice

An electron has what charge?

• Positive

• Negative

• Zero

All life wants balance. A charge of zero.

An ion is an atom, or compound, that has a charge.

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​How did they get these charges??

​What is an Ion?

The two ion types

​Some text here about the topic of discussion.

​Cation

• has a + charge

  • ​Why?

• ​Prefix cat- comes from greek, meaning down, inferior, wrong

Anion

• Has a - charge

  • ​Why?

​Ionic Radius Trend

​Explain why each ion type found to the right is the way it is.

Ionization Energy

The amount of energy it takes to remove an electron from an atom, resulting in an ion

​

​Higher energies mean that the atom has a stronger hold on its electrons

Definition

Multiple Choice

Refresh: Which ion type has a positive charge?

• Anion

• Cation

Multiple Choice

How does a cation get its positive charge?

• It gains an electron

• It loses and electron

Octet Rule

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• At most, each shell can hold 8 valence electrons. Except the first shell holds 2

• ​Therefore, ions are created as each element attempts to gain the maximum valence electrons

• ​Lithium looses one to become a cation and therefore satisfy the rule

​Each Atom Wants To Be Stable

Electronegativity

​Some text here about the topic of discussion.

• Flourine is the most electronegative element

  • ​Why flourine and not chlorine??

  • ​Because of the nucleus charge. Remember that positive and negative ends of a magnet attract.

The ability of an atom to attract an electron