Pauli exclusion principle
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The document discusses the Pauli Exclusion Principle and its importance in the periodic table. It explains that the principle states that no two electrons in an atom can have the same set of quantum numbers, and electrons must have opposite spins when occupying the same orbital. This principle allows electrons to be arranged in shells and is crucial for determining an element's chemical properties and for constructing the periodic table by blocks.
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Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
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Pauli exclusion principle
- 1. PAULI EXCLUSION PRINCIPLE 1-Pauli Exclusion Principle 2-Uses of the principle in periodic table May 2019
- 2. Presented to:- Prof. Dr. M. Irfan Presented by:- Muhammad Imran Muhammad Sohail Muhammad Salahuddin Muhammad Shakeel Tanveer Azmat 2
- 3. Concept of Shells & Subshells These are actually the residing places of electrons in an atom. Shells are energy levels around the nucleus of an atom. These are subdivided into sub-energy levels called subshells Shells and Subshells are called orbits and orbitals respectively. Shells are designated with numbers as n=1,2,3,… and named as K,L,M… in correspondence. 3
- 4. Intro to Orbitals Also Known as Subshells or sub energy levels. They are named as s, p, d, f and so on with numeric values as 0,1,2,3….. Every Orbit has fixed number of orbitals Every orbital has fixed capacity to place electrons For Example s has 2, p =6, d=10 and f=14. These orbitals have subdivisions to occupy electrons and each subdivision can have only two electrons in it. 4
- 5. PAULI EXCLUSION PRINCIPLE Based upon the previous electronic management in an atom we’ll try to explain the above mentioned principle Principle states that:- Orbital can hold maximum of two electrons If two electron in an orbital, must have opposite spin Two possible spins are clockwise and anticlockwise or simply up and down 5
- 6. Quantum Numbers There are four quantum numbers which help in the explanation of atomic structure and construction of periodic table. Those are:- Principle Quantum Number (n) where n= 1, 2, 3,….. Azimuthal Quantum Number(l) where l= 0, 1, 2,……. Spin Quantum Number(s) where s= +(1/2) & -(1/2) Magnetic Quantum Number(m) where m= 0,±1,±2,………. 6
- 7. Construction Of Periodic Table & Pauli Exclusion Principle The construction of the existing periodic table would not have been possible without “the Pauli Exclusion Principle”. But we also need to utilize and follow following rules:- Hund’s Rule Aufbao Principle The above mentioned two rules along with the exclusion principle help in construction of periodic table. 7
- 8. 8 Main points for construction of Periodic Table Filling of Electrons in Shells/Subshells/sublevels( “/” shows path) Energy wise Sequence of Electronic Configuration Placement of elements in respective Blocks
- 9. 9 Filling of Electrons in Shells/Subshells/sublevels Considering Shell 2 or L with n=2, l=0,1 m=0,±1
- 10. 10 Energy wise Sequence of Electronic Configuration • Electronic Configuration refers to the distribution of electrons in shells and subshells according to their increasing energy levels or simply depending upon the energy of sublevels
- 11. 11 Here is the trick for energy wise sequence
- 12. 12 Placement of elements in respective Blocks The periodic table is styled with a block distribution of the elements depending upon their chemical properties which is directly governed by electronic configuration of the shells, ultimately Pauli Exclusion Principle stood responsible for the chemical properties of elements and development Periodic table. Following Picture shows the blocks along with configuration:-
- 13. 13 Blocks in Periodic Table
- 14. 14 Importance Of Pauli Exclusion Principle If this principle were not valid, an atom could radiate energy until every electron in the atom is in the lowest possible energy state and therefore the chemical behavior of the elements would be grossly modified. Nature as we know it would not exist. That’s the importance of Pauli Exclusion Principle in the construction of periodic table.