1. Iron group
   Zinc group
2. Noble gases
   Cobalt group

Cadmium's atomic number is 48. As with other elements in the zinc group, cadmium has a valence electron count of 2.

1. Nickel group
   Group 7
2. Cobalt group
   Pnictogens

Group 7 includes the elements manganese, technetium and bohrium as well as rhenium which are transition metals. Manganese is the most common element in the group.

1. Iron
   Titanium
2. Argon
   Sodium

The helium or neon family is group 18 in the periodic table. Elements in this group are referred to as noble gases or inert gases.

1. Iron group
   Nickel group
2. Carbon group
   Boron group

"Triels" is another name for elements in group 13, or the boron group, of the periodic table. This group contains elements such as boron, gallium and aluminium (or aluminum).

1. Group 2
   Group 11
2. Group 6
   Group 4

The symbol Cr stands for the element chromium, which belongs to group 6 in the periodic table. Elements in this group possess either one or two valence electrons. Tungsten is another member of this element group.

1. Dubnium
   Niobium
2. Helium
   Tantalum

The vanadium group is group 5 in the periodic table. Elements of this group are transition metals with a valence electron count of 2. Niobium is the only member with a valence electron count of 1.

1. Zinc group
   Cobalt group
2. Iron group
   Nickel group

Rhodium has an atomic number of 45 and the element contains 1 valence electron, whereas other elements in the cobalt group have a valence electron count of 2. Rhodium is an extremely rare element that exists in 4.6 percent of the native platinum metal compounds.

1. Iron group
   Coinage metals
2. Alkali metals
   Nickel group

The International Union of Pure and Applied Chemistry, or IUPAC, standardized modern naming conventions for previously inconsistent designations in the periodic table. The IUPAC group 8 is the iron group or iron family, which includes the transition metals ruthenium, iron, osmium and hassium.

1. Alkaline-earth metals
   Titanium group
2. Halogens
   Nitrogen group

D-block elements, also known as transition elements, have valence electrons in two shells instead of just one. Valence electrons enable the formation of chemical bonds. The titanium group is group 4 of the periodic table and includes hafnium, rutherfordium, zirconium and titanium.

1. Silver
   Lanthanum
2. Dysprosium
   Thulium

Lanthanides are 15 consecutive metals in the periodic table that are often called rare-earth elements. Typical valences are 3 and 4, and atomic numbers range from 57 to 71. Silver has an atomic number of 47.

1. Calcium
   Scandium
2. Phosphorus
   Iodine

Calcium is the fifth most abundant element in the Earth's crust. Other alkaline-earth metals include beryllium, radium, barium, magnesium and strontium.

1. Yttrium
   Nihonium
2. Plutonium
   Potassium

Plutonium has atomic number 94, which is within the range of elements, of atomic numbers 89 to 103, that include the actinide or actinoid elements. Actinide elements share radioactive traits.

1. Nickel
   Scandium
2. Vanadium
   Hassium

Scandium is a rare-earth metal that belongs to group 3 in the periodic table. Scandium is a reactive metal with 2 valence electrons.

1. Zinc family
   Coinage metals
2. Fluorine family
   Halogens

Group 11 in the periodic table contains the coinage metals that include copper, silver and gold. These elements all have a valence of 1 electron.

1. Niobium
   Lithium
2. Ruthenium
   Hydrogen

Hydrogen has atomic number 1 and is the lightest of the elements. Hydrogen is a reactive nonmetal and is one of two period 1 elements; Helium is the other.

1. Alkaline-earth metals
   Triels
2. Tetrels
   Alkali metals

Group 14 of the periodic table includes carbon, silicon, germanium, tin, lead and flerovium. Tetrels, from "tetra" which is the Greek for four, is another word for group 14 elements. Elements in this group have a valence of 4.

1. Chromium
   Arsenic
2. Barium
   Francium

Pnictogens, or pentels, are group 15 elements in the periodic table. Arsenic, as with the other congeners of this group, has 5 valence electrons.

1. Actinides
   Tetrels
2. Chalcogens
   Halogens

Chalcogens are also called the oxygen family or group 16 elements of the periodic table. Sulfur is the period 3 element with atomic number 16 in the chalcogen group.

1. Alkali metals
   Iron group
2. Cobalt group
   Boron group

Cesium has the symbol Cs and is a group 1 alkali metal in the periodic table. Cesium is one of the softest metals, and it is highly reactive.

1. Zinc family
   Titanium group
2. Coinage metals
   Silicon group

Silicon is the second element in the carbon group, which is also group 14 of the periodic table. Coinage metals are group 11 elements. A group in the periodic table is also described as a "family."

1. Pentels
   Alkaline-earth metals
2. Period 6
   Noble gases

Strontium is an alkaline-earth metal within the period 5 elements of the periodic table. This element has an oxidation state of +2. Sixteen radioactive isotopes have been derived from strontium through nuclear reactions.

1. Halogens
   Bromides
2. Tetrels
   Noble gases

The six halogens are bromine, chlorine, fluorine, iodine, tennessine and astatine. All halogen elements produce sodium salts. Sodium chloride is one example.

1. Radon
   Bismuth
2. Dubnium
   Hafnium

Hafnium is one of four elements in group 4 of the periodic table. Hafnium's oxidation state is +4, and this metal has a high tolerance for corrosion.

1. Seven
   One
2. Six
   Eight

Group eleven elements include copper, silver, gold and roentgenium. With the possible exception of roentgenium, this group's elements share the same chemical traits which results from the common valence configuration.

1. Transition metals
   Metalloids
2. Noble gases
   Reactive nonmetals

Silicon, boron, germanium, arsenic, tellurium and antimony are considered metalloids. Currently, no conclusive description for a metalloid exists.

1. Noble gases
   Alkali metals
2. Alkaline-earth metals
   Transition metals

Noble gases are nonflammable gases. Except for helium and highly radioactive radon, all noble gases exist in the earth's atmosphere. Neon, argon, krypton and xenon are all noble gases.

1. F-block
   S-block
2. D-block
   P-block

Group 1 and group 2 elements, as well as helium, are included in the s-block. Potassium is a group 1 alkali metal. The s-orbital electrons of s-block elements readily react with other elements to form compounds.

1. Zinc group
   Mercury group
2. Boron family
   Oxygen family

Cadmium and copernicium are the other elements in the zinc group. Mercury is the only metal in the group that is liquid at room temperature.

1. Chromium and molybdenum
   Helium and hydrogen
2. Tungsten and seaborgium
   Gold and potassium

Tungsten and seaborgium are elements in the chromium group with 2 valence electrons. Tungsten, chromium and molybdenum are refractory metals, which are durable and maintain structural properties at high levels of heat.

1. Nickel
   Manganese
2. Iron
   Cobalt

Manganese has an atomic number of 25 and five oxidation states: +2, +3, +4, +5, +6 and +7. Manganese forms a wide selection of compounds, including potassium permanganate, manganese oxide and manganese carbonate.

1. Arsenic and bismuth
   Phosphorus and nitrogen
2. Aluminum and gallium
   Calcium and radium

In addition to the benefits that phosphorus and nitrogen provide living things, these elements are also abundant in explosive weaponry. Bismuth, arsenic, antimony and moscovium are also group 15, nitrogen group elements.

1. Selenium
   Calcium
2. Rubidium
   Tantalum

Selenium is one of five reactive nonmetals that are solids. There are five reactive nonmetals that are gases, and one is a liquid.

1. Xenon
   Chlorine
2. Lanthanum
   Neon

The f-block of the periodic table includes period 6 lanthanides and period 7 actinides, which are all metals. F-block elements are also called inner transition metals.

1. Group 1
   Copper family
2. Boron group
   Coinage metals

Lithium has the symbol Li and atomic number 3. It's the first element of group 1, otherwise known as the lithium family. Group 1 elements are alkali metals.

1. Halogens
   Beryllium group
2. Tetrels
   Noble gases

Elements in group 2 of the periodic table are alkaline-earth metals that are also known as beryllium group elements. Alkaline-earth metal atoms readily lose electrons to become cations, or positive ions.