Physics Wallah

CBSE Class 11 Chemistry Notes Chapter 11 The p-Block Elements

Here, we have provided CBSE Class 11 Chemistry Notes Chapter 11 The p-Block Elements. Students can view these CBSE Class 11 Chemistry Notes Chapter 11 before exams for better understanding of the chapter.
authorImageNeha Tanna20 May, 2024
Share

Share

CBSE Class 11 Chemistry Notes Chapter 11

CBSE Class 11 Chemistry Notes Chapter 11: The CBSE Class 11 Chemistry Notes Chapter 11 are free to download on our website. The p-Block Elements CBSE Class 11 Chemistry Notes Chapter 11 are now available chapter-by-chapter here, the greatest online learning resource for CBSE students, to help them quickly prepare for their school-based yearly exams and CBSE exams. You may also obtain the Class 11, Chapter 11.

CBSE Class 11 Chemistry Notes Chapter 11 Overview

Six groups of p-block elements, numbered 13 through 18, with the electrical configuration ns2np1-6, are included in the periodic table. It contains every kind of element, including metal, non-metal, and metalloids. The differences in their electronic configuration's inner core have a significant impact on their chemical and physical properties. The group's lighter elements have a very consistent group oxidation state. The heavier elements have more stable lower oxidation states and produce dπ–dπ or dπ–pπ bonds. The lighter components, however, form pπ–pπ bonds. Second-period elements have a maximum covalence of 4, however heavier elements can have a greater value due to the lack of a d orbital.

CBSE Class 11 Chemistry Notes Chapter 11 PDF

The CBSE Class 11 Chemistry Notes Chapter 11 are available for download, and they will help students do well on tests. CBSE Class 11 Chemistry Notes Chapter 11 how a group of knowledgeable professors prepares chemistry in class 11. You may quickly revise the entire chapter with the aid of the revision notes. One of the best study techniques that lecturers recommend is going over your CBSE Class 11 Chemistry Notes Chapter 11 again on exam day.

CBSE Class 11 Chemistry Notes Chapter 11 PDF

CBSE Class 11 Chemistry Notes Chapter 11

The elements in groups 13 through 18 of the periodic table comprise the p-block. The p-block contains metals, metalloids, and non-metals. The p-block components have an electrical configuration similar to a general ns2np1−6 valence shell structure. The first members of each group from 13 to 17 of the p-block elements are distinct from the other members of their respective groups in numerous respects due to their small size, strong electronegativity, and lack of d-orbitals. In comparison to other members of the same group, the first member of a group is better able to form pπ−pπ multiple connections both to elements in the second row (e.g., C=O,C=N,C≡N,N=O) and to itself (e.g., C=C,C≡ C,N≡N). A p-block element's maximum oxidation is its group number minus 10. In groups 13 to 16, the oxidation state two less than the maximal group oxidation state becomes more stable because of the inert pair effect. (The reluctance of s-subshell electrons to form chemical bonds).

Trends in Properties of P-Block Elements

Trends in properties of p-block elements

(A) Group 13 Elements: The Boron Family

Aluminium is a metal that shares many chemical properties with boron, while gallium, indium, and thallium are almost fully metallic. Boron is a non-metal.

Electronic Configuration:

The valence shell electronic configuration of elements of boron family is n s 2 n p 1 ns2np1 .

Atomic Radii:

The atomic radius increases as one advances along the group because each consecutive member gains an extra electron shell. Compared to Al, Ga has a smaller atomic radius. An additional 10 d-electrons only slightly reduces the outer electrons' screening effect due to gallium's larger nuclear charge. Consequently, the atomic radius of gallium (135 pm) is smaller than that of aluminium (143 pm).

Ionization Enthalpy

The general patterns predict that the ionisation enthalpy values will drop smoothly along the group, however this is not the case. The decrease from B to Al corresponds with size increases. The discontinuity in ionisation enthalpy values between Al and Ga and between In and Tl is caused by the d and f electrons' low screening effect, which makes them unable to offset the increase in nuclear charge. The first three ionisation enthalpies of each element add up to a very high value.

Electronegativity

As you go down the group, electronegativity decreases from B to Al and then considerably increases. This is because the atomic sizes of the various elements varies.

Physical Properties

The element boron is non-metallic. It is an extremely hard solid black hue. It is available in several allotropic forms. Boron's crystalline lattice strength gives it a very high melting point. The remaining group consists of soft metals with low melting points and strong electrical conductivity. Due to its low melting point (303K), gallium may be liquid in the summer. The high boiling point (2676K) of this substance makes it suitable for use in high temperature measurements. There is an increase in element density from boron to thallium.

Chemical Properties

Because boron is so little, its first three ionisation enthalpies add up to a very high value. Because of this, it is unable to create +3 ions and is only able to produce covalent compounds. But when we move from B to Al, the sum of Al's first three ionisation enthalpies decreases substantially, enabling Al to form Al+3 ions. Conversely, because of insufficient shielding, effective nuclear charge confines ns electrons tightly down the group, reducing their ability to participate in bonding. Thus, the p-orbital electron may be the only electron involved in bonding. Actually, reports of +1 and +3 oxidation states have been found for Ga, In, and Tl.

Reactivity Towards Air

As you progress through the group, these oxides take on different characteristics. When boron trioxide, an acidic chemical, reacts with basic (metallic) oxides, it creates metal borates. Aluminium and gallium oxides are amphoteric, whereas indium and thallium oxides are basic.

Reactivity Towards Acids and Alkalies

Although aluminium dissolves in mineral acids and aqueous alkalies, giving it an amphoteric quality, boron does not react with acids or alkalies, even at moderate temperatures. When aluminium is dissolved in diluted HCl, dihydrogen is produced. Conversely, concentrated nitric acid inactivates aluminium by covering the metal's surface with a layer of protective oxide. Dihydrogen is created when aluminium reacts with aqueous alkali.

Boron (B)

Uses:

Boron is utilised in the manufacture of high-impact steel and, since it absorbs neutrons, in reactor rods for atomic reaction control.

As a result, it acts as a Lewis acid rather than a proton donor. When a polyhydroxy molecule like glycol or glycerol is added to its aqueous solution, it behaves as a strong acid. The great stability of the conjugate bone chelate complex accounts for the acidity.

Formation of complex by glycol with orthoboric acid

Catechol and salicylic acids create comparable complexes, but ethanol does not.

Catechol and salicylic acids complexes with orthoboric acid

Orthoboric acid dissolves better in hot water than in cold, and it feels greasy to the touch. Planar units of BO3 are connected by hydrogen bonds to form a multilayer structure.

Multilayer structure ${\text{B}}{{\text{O}}_3}$ connecting planar units with hydrogen bonds

Uses:

It's an antiseptic, and the water solution may be used to cleanse your eyes. In addition, it is utilised in the glass, enamel, and pottery industries.

Preparation:

Aluminium

Extraction (Hall-Heroult Process)

Aluminium is extracted from the mineral ore known as bauxite (Al2O3⋅2H2O). To start, the ore is first purified using Bayere's technique. Al2O3 that is anhydrous is mixed and fused. Electrolytic reduction is applied to the fused combination of Na3AlF6 & CaF2 when aluminium is obtained at the cathode. Aluminium is purified by Hoope's technique.

Uses

Aluminium is utilized for plating tanks, pipes, iron bars, and other steel items to prevent corrosion, manufacturing of aluminium cables, precise instruments, surgical apparatus, aircraft bodies, train coaches, motorboats, and automobiles.

Compounds of Aluminium

It's also known as alumina. It may be found in the form of bauxite and corundum in nature. It can also be found in gemstones. Topaz yellow, sapphire blue, ruby red, amethyst violet, and emerald green are some of the most important aluminium oxide stones.

Properties:

It's a white amorphous powder that's insoluble in water but soluble in acids (forming, for example AlCl3 ) and alkalies, making it amphoteric. It's a polar covalent molecule with a positive charge.

Uses:

It is employed in the extraction of aluminium, the creation of fake gems, the production of aluminium compounds, and the fabrication of furnace linings. As a catalyst in organic processes, it is a refractory substance.

Oxidation States and Trends in Chemical Reactivity

Group 14 elements consist of four electrons in their outermost shell. The most common oxidation states for these elements are +4 and +2, along with carbon, which also exhibits negative oxidation states. Because the total of the ionisation enthalpies of the first four compounds is quite big, compounds at the +4 oxidation state are often covalent in nature. Higher in the sequence Ge<Sn<Pb, heavier components are more likely to exhibit the +2 oxidation state. It results from the valence shell electrons' ns2 incapacity to form bonds. As one moves through the group, the relative stability of these two oxidation states changes. Only four times may carbon surpass its covalence. It is something that other gang members are capable of. The reason for this is that they contain the d orbital. As a result, their halides are hydrolyzed, and they tend to accept electron pairs from donor species to form complexes.

Allotropes of Carbon

There are several allotropic forms of carbon, including amorphous and crystallic forms. Graphite and diamond are two well-known crystalline forms of carbon. Fullerenes are a third type of carbon that were discovered in 1985 by H.W. Kroto, E. Smalley, and R.F. Curl.

Diamond

It has a crystalline structure. Using hybridised orbitals, each carbon atom in a diamond is joined to four other carbon atoms in a tetrahedral pattern after undergoing sp hybridization. The C-C bond has a length of 154 pm. Expanding into space, the structure forms a rigid, three-dimensional network of carbon atoms. In this structure, directional covalent bonds are present throughout the lattice. Due to its remarkable resistance to breaking long-lasting covalent bonds, diamond is the hardest material in the universe. In addition to being used to create colours and tungsten filament for light bulbs, it is employed as an abrasive to sharpen hard tools.

Graphite:

Graphite is a layered material. The layers are held together by van der Waal's forces, and there is 340 pm separating them. The carbon atoms in each layer are grouped into planar hexagonal rings. The C-C bond length in the layer is 141.5 pm. Every carbon atom in a hexagonal ring undergoes sp2 hybridization, resulting in the formation of three sigma bonds with neighbouring carbon atoms. And the fourth electron forms a π bond. The sheet is filled with scattered electrons. Graphite transfers electricity throughout the sheet because electrons are movable. Graphite cleaves easily between the layers, making it especially slick and smooth. Consequently, in machines that cannot utilise oil and must run at high temperatures, graphite is used as a dry lubricant.

Fullerenes:

Graphite is heated in an electrical arc with inert gases like argon or helium to produce fullerenes. Fullerenes are the only pure form of carbon due to its smooth shape and absence of "dangling" connections. One type of molecule that resembles a cage is called a fullerene. The C60 compound known as buckminsterfullerene resembles a football. This set consists of twelve five-membered rings and twenty six-membered rings. A ring with six members can be fused with any other ring that has six members, whereas a ring with five members can only be fused with other rings that have six members. Every carbon atom is identical and experiences sp2 hybridization.

Uses of Carbon

Plastic is mixed with graphite fibres to create composite materials that are lightweight and highly durable. Composites are used to make canoes, fishing rods, planes, and tennis rackets. Because graphite is a great conductor, it is utilised for industrial electrolysis and as electrodes in batteries. Acids and alkalies cannot be diluted using graphite crucibles. Activated charcoal is employed in air conditioning systems to control odour, water filters to eliminate organic pollutants, and hazardous gas absorbers. Carbon black finds application as a dark pigment in black ink and as a filler in automobile tyres. Coke is mostly used as fuel and as a reducing agent in metallurgy. A precious stone used in jewellery is the diamond.

Benefits of CBSE Class 11 Chemistry Notes Chapter 11

  • Additionally, all of these materials are available for download on our website. Students can use these files a day or two prior to the exam to help them prepare more effectively.
  • All necessary notes are available for free of charge.
  • Along with these, students can also receive the appropriate help with their syllabus, questions about any subject, and other related
A revision note is one that is extremely vital and can be created by students or by other outside providers. It is used to write down calculations, crucial information, and things to keep in mind. Additionally, because it is convenient, students can make the most of it by having it with them throughout tests.
CBSE Chemistry Notes for Class 11
CBSE Class 11 Chemistry Notes Chapter 1 – Some Basic Concepts of Chemistry
CBSE Class 11 Chemistry Notes Chapter 2 – Structure of Atom
CBSE Class 11 Chemistry Notes Chapter 3 – Classification of Elements and Periodicity in Properties
CBSE Class 11 Chemistry Notes Chapter 4 – Chemical Bonding and Molecular Structure
CBSE Class 11 Chemistry Notes Chapter 5 – States of Matter
CBSE Class 11 Chemistry Notes Chapter 6 –Thermodynamics
CBSE Class 11 Chemistry Notes Chapter 7 -  Equilibrium
CBSE Class 11 Chemistry Notes Chapter 8 – Redox Reactions
CBSE Class 11 Chemistry Notes Chapter 9 – Hydrogen
CBSE Class 11 Chemistry Notes Chapter 10 – The s-Block Elements
CBSE Class 11 Chemistry Notes Chapter 11-  The p-Block Elements
CBSE Class 11 Chemistry Notes Chapter 12 - Organic Chemistry
CBSE Class 11 Chemistry Notes Chapter 13 -  Hydrocarbons
CBSE Class 11 Chemistry Notes Chapter 14 - Environmental Chemistry

CBSE Class 11 Chemistry Notes Chapter 11 FAQs

Which chapter has highest weightage in chemistry Class 11?

They are Thermodynamics, Mole Concept, Ionic Equilibrium, Nuclear Chemistry, and Atomic Structure. The chapters with the most weightage are Chapter 12 Organic Chemistry and Chapter 13 Hydrocarbons, which have a combined weightage of 18 marks.

Is Class 11 chemistry difficult?

Chemistry is often considered one of the most challenging subjects in the Class 11 curriculum. It involves complex concepts and requires a solid foundation for success. One of the most effective tools for mastering chemistry is the use of comprehensive study materials and notes.

Which is the hardest chapter in Class 11 chemistry?

Thermodynamics and Equilibrium are considered the toughest chapters.
Join 15 Million students on the app today!
Point IconLive & recorded classes available at ease
Point IconDashboard for progress tracking
Point IconMillions of practice questions at your fingertips
Download ButtonDownload Button
Banner Image
Banner Image
Free Learning Resources
Know about Physics Wallah
Physics Wallah is an Indian edtech platform that provides accessible & comprehensive learning experiences to students from Class 6th to postgraduate level. We also provide extensive NCERT solutions, sample paper, NEET, JEE Mains, BITSAT previous year papers & more such resources to students. Physics Wallah also caters to over 3.5 million registered students and over 78 lakh+ Youtube subscribers with 4.8 rating on its app.
We Stand Out because
We provide students with intensive courses with India’s qualified & experienced faculties & mentors. PW strives to make the learning experience comprehensive and accessible for students of all sections of society. We believe in empowering every single student who couldn't dream of a good career in engineering and medical field earlier.
Our Key Focus Areas
Physics Wallah's main focus is to make the learning experience as economical as possible for all students. With our affordable courses like Lakshya, Udaan and Arjuna and many others, we have been able to provide a platform for lakhs of aspirants. From providing Chemistry, Maths, Physics formula to giving e-books of eminent authors like RD Sharma, RS Aggarwal and Lakhmir Singh, PW focuses on every single student's need for preparation.
What Makes Us Different
Physics Wallah strives to develop a comprehensive pedagogical structure for students, where they get a state-of-the-art learning experience with study material and resources. Apart from catering students preparing for JEE Mains and NEET, PW also provides study material for each state board like Uttar Pradesh, Bihar, and others

Copyright © 2025 Physicswallah Limited All rights reserved.