Periodic Trends and Structure of the Periodic Table

What are the two main orientations of the Periodic Table?

Rows (Periods) and Columns (Groups or Families)

What do elements in the same group have in common?

They have similar chemical properties due to having the same number of electrons in their outer shell.

What is the classification of elements that are good at conducting heat and electricity?

Metals

What is the defining characteristic of nonmetals?

Poor conductors of heat and electricity, usually brittle when solid.

What term describes elements that share properties of both metals and nonmetals?

Metalloids

How does atomic radius change across a period?

Atoms get smaller.

What happens to atomic radius down a group?

Atoms get bigger as more electron shells are added.

What trend occurs with ionization energy as you move across a period?

It becomes harder to remove an electron.

What trend occurs with ionization energy down a group?

It gets easier to remove an electron.

What is the trend of electron affinity across a period?

Atoms want to gain electrons more as they get closer to having a full outer shell.

What happens to electron affinity as you move down a group?

Atoms want to gain electrons less.

What are the characteristics of Alkali Metals?

Very reactive, especially with water, and have one electron in their outer shell.

What do Alkaline Earth Metals have in common?

Reactive but not as much as alkali metals, with two electrons in their outer shell.

What defines Transition Metals?

Less reactive, can form colorful compounds, and have different ways to bond.

What is a key characteristic of Halogens?

Very reactive nonmetals with seven valence electrons.

What defines Noble Gases?

Very stable, do not react because they have a full outer shell.

How does metallic character change across a period?

Metals change to nonmetals.

How does non-metallic character change down a group?

Nonmetals become less like nonmetals.