In the periodic table, there are different ways to categorize the element families. One way is to categorize them as 5 element families, Alkali metals, Alkaline earth metals, Transition metals, Halogens, and Noble gases. There is another method of categorization that recognizes nine element families, Alkali Metals: Group 1 (IA) - 1 valence electron, Alkaline Earth Metals: Group 2 (IIA) - 2 valence electrons, Transition Metals: Groups 3-12 - d and f block metals have 2 valence electrons, Boron Group or Earth Metals: Group 13 (IIIA) - 3 valence electrons, Carbon Group or Tetrels: - Group 14 (IVA) - 4 valence electrons, Nitrogen Group or Pnictogens: - Group 15 (VA) - 5 valence electrons, Oxygen Group or Chalcogens: - Group 16 (VIA) - 6 valence electrons,Halogens: - Group 17 (VIIA) - 7 valence electrons, Noble Gases: - Group 18 (VIIIA) - 8 valence electrons.
The columns of the periodic table mark groups or families, in which there are three systems that have been used to number families and groups. The first one is the older IUPAC system that used Roman numerals together with letters to distinguish between the left and right sides of the periodic table. Secondly is the CAS system that used letters to differentiate main group and transition elements. Lastly is the modern IUPAC system that uses Arabic numbers 1-18, simply numbering the columns of the periodic table from left to right. Many periodic tables use both Roman and Arabic numbers, but the Arabic numbering system is the most widely accepted today.
Group 1 or IA
Alkali Metals:
- High thermal and electrical conductivity
- Low densities, increasing with atomic mass
- Relatively low melting points, decreasing with atomic mass
- Vigorous exothermic reaction with water to produce hydrogen gas and an alkali metal hydroxide solution
- Ionize to lose their electron, so the ion has a +1 charge
- Some examples include Sodium and potassium, and under the right conditions of temperature and pressure, hydrogen can be an alkali metal.
Next is Alkaline Earth Metals or Group 2 Family of Elements
Group 2 or IIA
Alkaline Earth Metals (Alkaline Earths):
- Metallic solids, harder than the alkali metals
- Shiny, lustrous, oxidize easily
- High thermal and electrical conductivity
- Denser than the alkali metals
- Higher melting points than alkali metals
- Exothermic reaction with water, increasing as you move down the group; beryllium does not react with water; magnesium reacts only with steam
- Ionize to lose their valence electrons, so the ion has a +2 charge
- Some examples include calcium and magnesium.
Next is the Boron Group or Earth Metal Family of Elements.
Group 13 or IIIA
Boron Group or Earth Metals:
- Diverse properties, intermediate between those of metals and nonmetals
- Best-known member: aluminum
Then we have the Carbon Group or Tetrels Family of Elements.
Group 14 or IVA
Carbon Group or Tetrels:
- Diverse properties, intermediate between those of metals and nonmetals
- Best-known member: carbon, which commonly forms 4 bonds
Next, we have the Nitrogen Group or Pnictogens Family of Elements.
Group 15 or VA
Nitrogen Group or Pnictogens:
- Diverse properties, intermediate between those of metals and nonmetals
- Best-known member: nitrogen
Then we have the Halogen Family of Elements.
Group 17 or VIIA
Halogens:
- Melting points and boiling points increase with increasing atomic number
- Changes state as it moves down the family, with fluorine and chlorine existing as gases at room temperature while bromine is a liquid and iodine is a solid
Last but not least we have the Noble Gas Element Family.
Group 18 or VIIIA
Noble Gases or Inert Gases:
- Typically exist as monatomic gases, although these elements rarely form compounds
- Stable electron octet makes nonreactive inert under ordinary circumstances
Hope this helps, sorry it's a lot.
