Class 11 Chemistry Revision Notes for Chapter 3 - Classification of Elements and Periodicity in Properties - Free PDF Download
Chemistry Class 11 Chapter 3 is crucial for Board and competitive examinations as it deals with chemical bonding and periodicity. Class 11 Chemistry Chapter 3 Notes by Vedantu explain the concepts of elements and periodic classification. Generally, an electronic configuration helps in classifying elements into a periodic table. Classification of Elements and Periodicity in Properties Class 11 Notes Details about the classification like d-block, p-block, s-block and f-block. This is based on metals and components which are arranged based on numbers. Ideally, the top elements are non-metals having a value less than 20.
Topics Covered in Chapter 3 Classification of Elements and Periodicity in Properties of CBSE Class 11 Chemistry
Students looking for notes on Classification of Elements and Periodicity in Properties must know the topics covered in this chapter according to the latest syllabus prescribed by the CBSE. Below given are the topics covered in Chapter 3 Classification of Elements and Periodicity in Properties of CBSE Class 11 Chemistry.
1. Why do we need to classify elements?
2. Genesis of periodic classification
3. Modern Periodic Law and Present Form of the Periodic Table
4. Nomenclature of Elements with Atomic Numbers > 100
5. Electronic configuration of Elements and Periodic Table
Electronic Configurations in Periods
Groupwise Electronic Configurations
6. Electronic Configuration and Types of Elements: s-, p-, d- and f- Blocks
The s-Block Elements
The p-Block Elements
The f-Block Elements (Inner-Transition Elements)
The d-Block Elements (Transition Elements)
Metals, Nonmetals and Metalloids
7. Periodic Trends in Properties of Elements
Trends in Physical Properties (Atomic Radius, Ionic Radius, Ionisation Enthalpy, Electron Gain Enthalpy, Electronegativity)
Periodic Trends in Chemical Properties
Periodicity of Valence or Oxidation States
Anomalous Properties of Second Period Elements
Periodic Trends and Chemical Reactivity
FAQs on Classification of Elements and Periodicity in Properties Class 11 Notes CBSE Chemistry Chapter 3 [Free PDF Download]
1. What are an Isolated Gaseous Atom and Ground State in an Ionisation Enthalpy and Electron Gain Enthalpy?
The isolated gaseous atoms are forms of revolting and attractive conditions of interaction that are far separated. This property makes it in an isolated form hence naming it isolated atoms. The value of electron gain enthalpy and ionisation enthalpy don’t get involved with particles. The interatomic forces further make it impossible to express the state of particles that is solid, gaseous or liquid.
The ground state of atoms shows the general state of energy in particles which is significant. This further implies that particles can have a lower form of power or neither slack nor add electrons in the process. Both electron gain enthalpy and ionisation enthalpy here is expressed via an atom’s ground state.
2. What are the Factors that Lead to a Decrease of a Group due to Ionisation Enthalpy of Main Group Elements?
The factors that lead to a decrease of a group due to ionisation enthalpy of main group elements are atomic size. The increase of nuclear size makes the electron shell number increase rapidly. This makes the force binding with electrons and nucleus decrease generally. Moreover, the ionisation enthalpy is affected rapidly as it starts to decrease with the increase of atomic size.
Here shielding or screening of electrons can be useful. The addition of new shells makes the numerous electrons inside the body that protects the electron valence increase. This change results in the diminishing of ionisation enthalpy, where the nucleus acts as an attraction force for valence electron reduction.
3. What is the Radius of an Atom When it Gains an Electron and Loses an Electron Respectively?
An anion is generally formed with the gain of electrons. This particle has a size that is larger than that of a parent atom. The reason is simple - multiple or single electrons result in augmented revulsion among electrons and the lowering of nuclear charge.
An example would be if Fluoride ion is 136 pm which is F-, and radius of atom in fluorine is 64 pm, forms a cation. This is because electrons start to loosen from an atomic reaction forming cation. It is smaller in size due to the previous electron where a charge of the nucleus is constant.
4. What is periodicity in properties, according to Chapter 3 of Class 11 Chemistry?
Repetition of the properties of elements after a given interval is referred to as periodicity of properties. When the elements are organised in the increasing order of the atomic number of the periodic table, the elements will repeat their characteristics after a definite period of time. The periodic properties are thoroughly explained in the revision notes for Chapter 3 of Class 11 Chemistry which is available free of cost on the Vedantu website and the Vedantu app.
5. What is the name of Chapter 3 of Class 11 Chemistry?
The Chapter 3 of Class 11 Chemistry is Called "Classification Of Elements And Periodicity In Properties". This Chapter is important for the Class 12 boards and the competitive exams such as NEET and JEE. You can find complete answers to this Chapter from the NCERT by Vedantu. These solutions are created by experts and are available for free.
6. What does atomic radius and ionic radius mean, according to Chapter 3 of Class 11 Chemistry?
Atomic radius: The measurement from the centre of the nucleus of an atom till the last shell of electrons of any given element is referred to as the atomic radius. It can imply both covalent and metallic radius based on whether the element is a metal or a nonmetal.
Ionic radius: The Ionic radii may be calculated by measuring the distance between the cations and the anions in an ionic crystal.
7. Explain why cations are smaller and anions larger in radii than their parent atoms, according to Chapter 3 of Class 11 Chemistry?
A cation has to be smaller than its parent atom since it has few electrons, but the nuclear charge remains the same. The anions have to be larger than the parent atom because the extra one or more than one electron would lead to increased repulsion between the electrons and a reduction in the nuclear charge.
8. What are the various factors due to which the ionization enthalpy of the main group elements tends to decrease down the group, according to Chapter 3 of Class 11 Chemistry?
Atomic size: With an increase in the atomic size, there is also an increase in electron shells. Thus, the force binding the electrons with its nucleus reduces. Thus the ionization enthalpy reduces with an increase in the atomic size.
Shielding effect of inner shell electrons: Given the addition of the new shells, there is an increase in the quantity of the inner electron shells that shield the valence electrons. Therefore, the power of attraction of the nucleus for these valence electrons decreases further, and thus the ionization enthalpy also decreases.