p-block elements are those periodic table elements whose last valence electron goes into any of the three p orbitals. Since there are three p orbitals, each occupying up to two electrons, the maximum number of electrons in the p subshell is six. Therefore, there are six groups of p-block elements ^[1-4].

Location

p-block elements are located on the right-hand side of the periodic table. Their group numbers range from 13 to 18. Group 13 elements have one p-orbital electron, Group 14 elements have two, and so on. Despite lying in Group 18, helium is not considered a p-block element. It is a s-block element ^[1-4].

Characteristics

p-block elements consist of metals, nonmetals, and metalloids. Since the elements are spread over various groups, their properties vary considerably. The first row of p-block elements obeys the octet rule. The rest of them are hypervalent, which means they can accommodate more than eight electrons in their valence shell. The p-block elements have multiple oxidation states, usually varying by multiples of two ^[1-4].

Electron Configuration

Valence Shell Electron Configuration

Group Number	Group Name
Group 13	Boron family	ns2np1
Group 14	Carbon family	ns2np2
Group 15	Nitrogen family	ns2np3
Group 16	Oxygen family (The chalcogens)	ns2np4
Group 17	Halogen family	ns2np5
Group 18	Nobel gases	ns2np6, except helium, whose electron configuration is 1s2

Properties ^[1-4]

1. The p-block element’s penultimate shell consists of 2, 8, or 18 electrons.
2. Except for inert gases, p-block elements have a wide range of oxidation states. They run from +n to (n-8). Here, n is the number of electrons in the outermost shell.
3. The p-block elements have covalency, but higher members can have electrovalency. Highly electronegative elements, like fluorine, chlorine, and other halogens, display electrovalency by accepting electrons and forming anions. Some p-block elements also have coordinate valency.
4. The non-metallic character of the elements increases from left to right over a period. It decreases from top to bottom down a group.
5. Ionization energies increase from left to right across a period and decrease from top to bottom down a group. Because of the half-filled and fully-filled orbitals in the valence shell, members of groups 15 and 18 have very high ionization energies.
6. The reducing tendency decreases from left to right across a period, whereas oxidizing nature increases. Halogens are strong oxidizers.
7. Most p-block elements react with oxygen to form acidic oxides. The acidic character increases from left to right across a period.
8. Unlike s-block elements, no p-block elements nor their salts impart a distinct color to a flame.
9. Several p-block elements exhibit a phenomenon called allotropy. Carbon, silicon, phosphorus, sulfur, boron, germanium, tin, and arsenic are known to display this property.
10. Many p-block elements display catenation properties. These include carbon, silicon, germanium, nitrogen, oxygen, and sulfur.