Periods and Families

The periodic table is organized into 7 horizontal rows (called periods), and 18 vertical columns (called families).

Periods

A period is a horizontal row on the periodic table. In each period, the atomic numbers (and protons) of each element increase from left to right.

Elements in the same period have the same number of electron shells.

families

A family (also known as group) is a vertical column on the periodic table.

Elements in the same family have the same number of valence electrons and similar chemical properties.

Protons

A proton is a subatomic particle with a positive charge. It has a mass of approximately 1 amu (atomic mass unit), and is found in the nucleus of an atom.

The number of protons also equals the atomic number of an element. The periodic table is organized in order of increasing atomic number (proton number).

Metals, Non-Metals, and Metalloids

Location

Metals are everything to the left of the "stair-step line" (exc. Hydrogen).

Non-Metals are everything to the right of the "stair-step line", as well as Hydrogen.

Metalloids (also known as semimetals) make up the "stair-step line", beginning with Boron, and extending down to Astatine.

-Solid at Room Temperature (exc. Mercury)

-Dense (exc. Lithium, Potassium, Sodium)

-Corrodes/Oxidizes in air/sea water

-Good Heat/Electricity Conductors

-High Luster (shiny)

-High Melting Point

-Malleable

-Ductile

Properties of Metals

Properties of Metalloids

-Dull or Shiny

-Semiconductors

-Often exist in several forms

-Often Ductile

-Often Malleable

Properties of Non-Metals

-Dull

-Brittle

-Less dense

-Often gases

-Low melting point of solids

-Insulators (poor conductors)

Valence Electrons

Valence electrons are the electrons on the valence shell (outer-most shell) of an atom. This can be observed through a Bohr Model.

The number of valence electrons determines the family of an element (exc. transition metals).

Valence electrons are the part of the atom that is responsible for chemical bonding, which determining reactivity/chemical properties.

The valence shell is "full" when it has 8 atoms in it (exc. Hydrogen/Helium with only 1 electron shell; only elements 1-18).

When a valence shell is full, the atom is not reactive. However, when the valence shell is incomplete, the atom wants to lose/gain electrons to be full, so it is reactive.

Family I.

Alkali

Metals

Alkali Metals

The Alkali Metal Family consists of the elements Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Caesium (Cs), and Francium (Fr).

The Alkali Metals are "Group 1", and all of the elements have 1 valence electron.

Characteristics

Highly Reactive

(One Valence Electron; Not found freely in nature ; Explosive in water)

Soft

(Compared to most metals)

Metal Characteristics

Because Alkali Metals are classified as metals, they have properties of most metals (Pg. 8)

EX: Dense, Conductors, Luster, Malleable, Ductile

Common Uses

-Lithium is used in lubricants and batteries.

-Potassium is used in creating fertilizer.

-Sodium bicarbonate (baking soda) is used in cleaning, deodorizing, and cooking.

Bohr Models

Lithium

Potassium

Family II.

Alkaline

Earth Metals

Alkaline Earth Metals

The Alkaline Earth Metal Family consists of the elements Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra).

The Alkaline Earth Metals are "Group 2", and all of the elements have 2 valence electrons.

Characteristics

Reactive

(2 Valence Electrons ; Not found freely in nature ; Not AS reactive as Alkali M. ; Reacts to Halogens)

Silvery-white; Soft

(Harder than Alkali Metals)

Metal Characteristics

Because Alkaline Earth Metals are classified as metals, they have properties of most metals (Pg. 8).

EX: Dense, Conductors, Luster, Malleable, Ductile

Common Uses

-Calcium oxide is used in toothpaste, chewing gum, and vitamins.

-Strontium is used in fireworks and flares.

-Calcium carbonate is used in the construction industry (limestone, marble, chalk, coral).

Bohr Models

Beryllium

Magnesium

Family III.

Transition

Metals

Transition Metals

The Transition Metal Family consists of elements such as Copper (Cu), Iron (Fe), Nickel (Ni), Zinc (Zn), Cobalt (Co), Gold (Au), Manganese (Mn), and Silver (Ag).

The Transition Metals are "Groups 3-12", and the number of valence electrons vary.

Characteristics

Relatively Stable

(Compared to Alkali + Alkaline Earth Metals ; EXC: Lanthanides and Actinides)

Colored Compounds/Ions ; Magnetic

All Magnetic Elements are Transition: Ni, Co, Fe

Metal Characteristics

Because Alkaline Earth Metals are classified as metals, they have properties of most metals (Pg. 8).

EX: Dense, Conductors, Luster, Malleable ; Ductile

Common Uses

-Copper is used in cooking pots, plumbing pipes, roofing tiles, musical instruments, and electric wires.

-Iron is used in tools and vehicles.

-Silver is used in photograph developing.

-Gold, Silver, Platinum, and Copper are used to create jewelry.

Bohr Models

Scandium

Iron

Family IV.

Boron

Family

Boron Family

The Boron Family consists of the elements Boron (B), Aluminium (Al), Gallium (Ga), Indium (In), Thallium (Ti), and at times, Nihonium (Nh).

The Boron Family are "Group 13", and all of the elements have three valence electrons.

Characteristics

Slightly Reactive

(3 Valence Electrons ; Heavy Elements = Reactive ↑)

Soft

EXC: Boron

Metal/Metalloid Characteristics

The entire Boron Family (EXC: Boron) are classified as metals (Pg. 8). Boron has properties of metalloids (Pg. 9).

EX: Dense, Conductors, Luster, Malleable, Ductile ; EX: Poor Conductor

Common Uses

-Boron is used in ceramics, soap, flare guns, and fiberglass.

-Gallium is used in LED Lighting.

-Indium tin oxide is found in solar panels, road lights, and windshield glass.

-Aluminum is used in electrical gadgets, and vessels for cooking/safeguarding food (foil).

Bohr Models

Boron

Aluminum

Family V.

Carbon

Family

Carbon Family

The Carbon Family consists of the elements Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), Lead (Pb), and Flerovium (Fl).

The Carbon Family are "Group 14", and all of the elements have 4 valence electrons.

Characteristics

Relatively Stable

(4 Valence Electrons)

Poor Conductors/High Melting/Boiling Points

Although the Carbon Family has two metals, both are relatively poor conductors (Sn, Pb).

Non-Metal/Metal/Metalloid Characteristics

This group has Non-Metals, Metals, and Metalloids. Characteristics of each are found on Pg. 8, 9, 10.

Common Uses

-Silicon is the main component in the glass industry. Compounds of it are also used in computer chips and solar cells.

-Carbon is the basis of life.

-Germanium is used in the computer industry.

Bohr Models

Carbon

Silicon