Class 11 p Block Elements Notes

P block chemistry class 11 Notes

The class 11 inorganic chemistry aims to impart a thorough understanding of the periodic table which consists of 118 elements that are divided into blocks like p, s, d and f. NCERT chemistry class 11 has independent chapters on each of the blocks. The 11th chapter of class 11 chemistry takes us through the various properties of p block elements. Let’s get started and understand this chapter through our simple class 11 p block elements notes.

Understanding p Block Elements

The chemical components from Boron to Oganesson in groups 13 to 18 belong to the p-block elements. The electronic configuration, which denotes the distribution of orbitals, is ns2np1-6 for all the elements from Boron to Fluorine to Oganesson, and Helium alone takes 1s2. The inner core has a massive effect on the chemistry of the elements. The inner core electrons of the p block elements impose enormous clout on the elements’ physical and chemical properties. The p block elements are innately metals, metalloids and nonmetals. The table mentioned below showcases the electronic configuration along with the oxidation state of the p block elements. 

p Block Elements: Group 13 Elements

In our class 11 p block elements notes, the discussion begins with the topic of group 13 elements. The group 13 family has elements from Boron to Nihonium. The elements belonging to this group, majorly comprises metals and non metals elements. Let us now have a look at some of their distinguishing features-

Electronic Configuration
Electrons revolve around the nucleus. Through the electronic configuration, we can depict the area of the electrons around the spectra of the nucleus. The electronic configuration for the group 13 elements is ns2np1. The Boron family has a structure different from the other two families due to the composition of various cores. This, in turn, affects the intensity of the chemistry and other properties at various levels.

Also Read: Class 11 Thermodynamics

Atomic Radii
Atomic radius surges when moving from the Boron to the last element at an ascending rate. It increases as there is an increase in the energy levels around the nucleus.

Ionization Enthalpy
The next topic in our class 11 p block elements notes is ionization enthalpy. There are discrepancies in ΔH between Al, Ga, In, and Ti due to the inability of d and f electrons, ΔH = ΔiH1+ ΔiH2 + ΔiH3

The electronegativity depletes between B and Al but gradually increases after these elements.

p Block Elements: Physical Properties

All the elements other than the Boron possess similar characteristics. The following table contains a distinction between essential properties of boron and other elements-

Boron Other Elements
Nonmetal Soft metal
High melting point Low melting point
Low electrical conductivity Low electrical conductivity

p Block Elements: Chemical Properties

The p block elements reflect almost the same chemical properties. However, there are some exceptions. Listed below are the major parameters for stating the chemical properties in our class 11 p block elements notes-

Oxidation State

The sum of the s and p orbital electrons equals the oxidation state of the p-block elements. Apart from the oxidation state, p block elements might also exhibit other oxidation states called group oxidation states. Between the two, the oxidation state is more stable for the heavy elements. 

The following table contains the oxidation states for the Boron family among the other groups of the p-block elements.

Class 11 p Block Elements Notes

Analysing the table, you can notice the constant difference in the oxidation state values across the family elements. When the oxidation state is +1 for the Boron family, the group oxidation state increases by 2.  The oxidation state of the elements escalates in the following manner: Ti> In > Ga > Al. The order infers that the +1 oxidation state increases for the heavier elements steadily. The +1 oxidations are more ionic.


Next in our class 11 p block elements notes is Boron family element’s chemistry with various external bodies.

Air Heating Boron and Aluminiumevolves B2O3  and Al2O3. 2E(s) + 3O2 (g) ⎯⎯→ 2E2O3 (s)2E(s) + N2 (g) ⎯⎯→ 2EN (s)
Acids and alkalis Al fuses with acids and transforms into a hydroxide or oxide compound. 2Al(s) + 6HCl (aq) → 2Al3+ (aq) + 6Cl– (aq) + 3H2 (g)
Halogens Reactions produce trihalides. 2E(s) + 3 X2 (g) → 2EX3 (s)

Class 11 Chapter 10 S Block Elements

Important Compound of Boron: Orthoboric Acid

Orthoboric acid is a soap-like crystalline solid with a high level of solubility in hot water. Acidification of aqueous solution turns into boric acid.

Na2B4O7 + 2HCl + 5H2O → 2NaCl + 4B(OH)3 

Hydrolysis of halides and hydrides also form Boric acid.

Class 11 p Block Elements Notes

p Block Elements: Group 14 Elements

While going through the class 11 p block elements notes, the next topic now is the group 14. The group 14 elements are called Carbon Family. Elements in this group are: 

  • Carbon (C)
  • Silicon (Si)
  • Germanium Ge)
  • Lead (Pb)

The aforementioned elements of the group 14 exist the forms like-

Elements Forms
Carbon Element state: Coal, graphite, and diamondCombined state: Metal carbonates, hydrocarbons, and CO2
Silicon Found in Ceramics, glass, and cement
Germanium Used in transistors
Lead Galena

Now that you are aware of the multiple forms in which the group 14 elements exist, let us go through some important features of these elements.

Electronic Configuration
The electronic configuration of the group 14 elements is ns2np2  

Covalent Radius
Carbon has the smallest radius among the group, whereas lead has a higher radius than Carbon and Germanium.

Ionization Enthalpy
Ionization enthalpy decreases down the group. Ionization enthalpy decreases from Si to Ge to Sn. ΔiH escalates from Sn to Pb.

Electronegativity of the elements of the 14th group is the next topic in our class 11 p block elements notes. The elements of group 14 have electronegativity higher than the group 13 elements family.

Also Read: What is Medicinal Chemistry?

Group 14 Elements: Physical Properties

The table mentioned below showcases the significant features of the physical properties of elements-

Element Properties
Carbon and silicon Nonmetals
Germanium Metalloid
Tin and Lead Soft metals

Group 14 Elements: Chemical Properties

Here are some important chemical properties which the elements of group 14 exhibit.

Oxidation States
The elements have common oxidation states. Carbon and Silicon show +4 and +2 oxidation states. Germanium produces good compounds in +4 and fewer compounds in +2 oxidation states.Tin forms great compounds in both +4 and +2 oxidation states.

p block Elements: Reactivity

Let us have a look at the reactivity of p block elements in our class 11 notes with respect to other metals, noble gases or elements.

When an element reacts with oxygen, it forms monoxides and dioxides. Oxides at higher oxidation states have more acidity than that of the oxides at lower oxidation rates.

Elements Oxides Nature
Carbon Carbon monoxide Carbon dioxide CO- NeutralCO2– Acidic
Silicon Silicon dioxide Acidic
Germanium Germanium oxide Germanium dioxide GeO- distinctly acidicGeO2– acidic
Tin Tin oxide  Tin dioxide SnO – AmphotericSnO2 Amphoteric
Lead Lead oxideLead dioxide  PbO- AmphotericPbOAmphoteric 

Carbon, silicon, germanium and lead do not react with water. Only the Tin element from the family can react with water.

Sn + 2H2O → SnO2 + 2H2

Carbon does not form halides. But, all the other members can evolve into halides like Silicon fluoride and germanium chloride. The halides are covalent except for the SnF4 and PbF4, as they are ionic. Germanium and lead can also give rise to dihalides like GeF2. The following equation shows how SiCl4  transforms into Si(OH4).

Class 11 p Block Elements Notes

Allotropes of Carbon

The final and one of the most essential topics in our class 11 p block elements notes is various allotropes of carbon. Carbon prevails in two forms, both crystalline and amorphous. This property is called the Allotropy. One of them is diamond and graphite. Below is a detailed analysis of these two compounds-


The diamond has a tough three-dimensional structure, with each atom having a bond with three other carbon atoms. sp3 hybridization helps the atoms to link in tetrahedral fashion, and the covalent bond between the atoms occurs. The C-C link length is about 154 pm.


Bond occurs between atoms by sp2 hybridization, and the electrons are dynamic. This makes the graphite conductive. The distance between the atoms in the vertical fashion is 340 pm, and the horizontal distance is 141.5 pm.

Class 11 p Block Elements Notes

Thus, we hope that through these detailed class 11 p block elements notes, you have now completely understood the topic. Get in touch with our Leverage Edu experts and now how you can pave your way to the dream career as early as in class 11th. 

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