Periodic table configuration

What are the vertical columns in the periodic table called?

Groups or families

What are the horizontal rows in the periodic table called?

Periods

How many groups are in the periodic table?

18 groups

How many periods are in the periodic table?

7 periods

Which elements are classified as lanthanides?

Elements in period 6

Which elements are classified as actinides?

Elements in period 7

What are the three main types of elements in the periodic table?

Metals, non-metals, and metalloids

What are the properties of metals?

Good conductors of heat and electricity, malleable, ductile, and most are solid.

What are the properties of non-metals?

Poor conductors, many are gases at room temperature, and most solid non-metals are brittle.

What are metalloids?

Elements that have properties of both metals and non-metals.

What are alkali metals?

Group 1 elements that are soft, silvery, and highly reactive with water.

What are alkaline earth metals?

Group 2 elements that are soft, silvery, harder than alkali metals, and form strong bases in water.

What are transition metals known for?

Having multiple oxidation states and forming colorful salts.

What are chalcogens?

Group 16 non-metals with 6 valence electrons, known for their biological roles.

What are halogens?

Group 17 non-metals that are very reactive and form strong acids in water.

What are noble gases?

Group 18 inert gases that have 8 valence electrons and are very unreactive.

What is the significance of valence electrons?

They determine the reactivity of an element and are located in the outermost energy level.

Why are alkali metals highly reactive?

They have 1 valence electron, which makes them unstable.

What do alkaline earth metals do to achieve stability?

They give away their 2 valence electrons.

How do halogens achieve stability?

They gain 1 electron to complete their octet.

What is an octet?

A complete valence shell of 8 electrons, which is desired for stability.

What is the electron arrangement in energy levels?

Electrons fill energy levels from the inside out, with the first level holding 2 electrons.

How many valence electrons do noble gases have?

8 valence electrons.

What is the pattern of electrons across a period?

The number of energy levels increases with each period.

What is the relationship between groups and valence electrons?

Elements in the same group have the same number of valence electrons.

What happens to the reactivity of elements as you move down a group?

Elements tend to become more reactive.