Module 3.1 Electron Theory PDF

MODULE MODULE 33 ELECTRICS FUNDAMENTALS...

MODULE MODULE 33 ELECTRICS FUNDAMENTALS Licence category B1, B2, and B2L Issue number 2 3.1: Electron theory 3.10: Magnetism 3.2: Static electricity and conduction 3.11: Inductance/Inductor 3.3: Electrical terminology 3.12: DC motor/generator theory 3.4: Generation of electricity 3.13: AC theory 3.5: Sources of DC electricity 3.14: Resistive (R), capacitive (C) and inductive (L) circuits 3.6: DC circuits 3.15: Transformers 3.7: Resistance/Resistor 3.16: Filters 3.8: Power 3.17: AC generators 3.9: Capacitance/Capacitor 3.18: AC motors “THIS PAGE INTENTIONALLY LEFT BLANK”  MODULE 3 ELECTRICS FUNDAMENTALS Licence category B1, B2, and B2L 3.1 Electron theory Module 3.1 Electron theory Certification statement and objectives These Study Notes comply with the syllabus of EASA Regulation (EU) No. 1321/2014 Annex III (Part-66) Appendix I, including the amendment Regulation (EU) 2023/989, and the associated Knowledge Levels as specified below: Knowledge Levels Part-66 A1 Objective B1 Ref. A2 B2 B3 A3 B2L A4 Electron theory 3.1 1 1 1 Structure and distribution of electrical charges within: atoms, molecules, ions, compounds. 1-2 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Table of contents Nature of matter ________________________________ 4 Structure of atoms ______________________________ 6 Protons ______________________________________ 6 Neutrons _____________________________________ 6 Electrons _____________________________________ 6 Electron arrangements __________________________ 8 Shells _______________________________________ 8 Subshells ___________________________________ 10 Ionisation ___________________________________ 10 Examples of electron arrangements _______________ 10 Valency _____________________________________ 12 Energy levels ________________________________ 16 Elements, ions and compounds __________________ 20 Elements ____________________________________ 20 Compounds _________________________________ 22 Conductors, semiconductors and non-conductors ____ 28 Summary ___________________________________ 32 1-3 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Nature of matter Atoms are the smallest particles of matter whose properties we Also, what we perceive as the mass of an object is related study in chemistry. However, from experiments done in the late directly to the number of protons and neutrons contained it. 19th and early 20th century it was deduced that atoms were made up of three fundamental sub-atomic particles. The simplest atom is hydrogen which has a single proton for a nucleus. An atom of lead, on the other hand, has 82 protons The early Greek philosophers proposed that all matter is made and 125 neutrons in its nucleus and so has 207 (125 + 82) up of incredibly small but discrete units (like the bricks in our times as much material or substance as an atom of hydrogen. wall example). Democritus (460 − 370 BC) was the first to call these units ‘atomos’. From this phrase came the term atom that The size of an atom bears no simple relation to the number of we use today. Atomos is a Greek phrase which means ‘not cut’ particles in its nucleus. A sodium atom, for example, with or ‘that which is indivisible’. 11 protons and 12 neutrons is approximately the same size as an atom of mercury with 80 protons and 121 neutrons. Atoms can neither be created nor destroyed during chemical reactions. In general, we can say that the size of an atom is determined by its electron orbits, its substance is determined by the total All atoms are, crudely speaking, the same size and can be number of protons and neutrons in its nucleus. thought to consist of two main parts. The outer part is composed of one or more orbits of electrons. These orbits make up most of the volume of the atom yet contributes practically nothing to its substance. The other part, located at the centre, is extremely small compared to the atom as a whole, yet essentially all of the real substance of the atom can be attributed to this small speck. We call this speck the nucleus. Further investigation revealed that the nucleus is actually composed of two kinds of particles of a roughly equal size and substance packed closely together. These nuclear particles are the proton and neutron. When we refer to the amount of material or substance in an object, we are really talking about the number of protons and neutrons in that object. 1-4 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory “THIS PAGE INTENTIONALLY LEFT BLANK” 1-5 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Structure of atoms Atoms cannot be seen with the naked eye, only recently has Electrons this been possible, with very powerful microscopes. However, Electrons are the smallest of the three sub-atomic particles. scientists have a good idea of how they behave in different Electrons are nearly 2,000 times smaller than protons and situations. Based on these ideas, they have developed a model neutrons. The electrons move in a zone around the atomic of what the atom looks like, to help us understand atoms better. nucleus at extremely high speeds, forming an electron cloud that is much larger than the nucleus. Have a look again at the The modern model of the atom teaches us that all atoms are diagram which shows a model of the atom to see this. made up of sub-atomic particles. Sub-atomic means ‘smaller than the atom’. Protons The protons are deep inside the atom, in a zone called the nucleus. The protons are said to be positively charged. When two protons get near each other, they push each other away. When an electron gets near a proton, they attract each other. Two electrons will also push each other away. Scientists use the word ‘charge’ to represent the property these particles have. We observe that: like charges repel (meaning the same charges push each other away); and opposite charges attract. Neutrons Neutrons are particles that are neither positively nor negatively charged. They are neutral. The neutrons together with protons form the tightly packed nucleus at the centre of the atom. 1-6 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory The sub-atomic components of atoms Electrons, neutrons, protons. 1-7 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Electron arrangements Shells The electrons are arranged in energy levels or shells around Electrons in the same orbit have the same energies. The the nucleus and with increasing distance from the nucleus. The electron orbits are also called electron energy levels or shells. shells are lettered from the innermost shell outwards from K to Electronic shells are known as K shell, L shell, M shell, N shell Q. There are rules about the maximum number of electrons corresponding to orbit number n=1, 2, 3 and 4 respectively. allowed in each shell. Higher number orbits are assigned shell names in alphabetical order after N. The 1st shell (K) has a maximum of 2 electrons The 2nd shell (L) has a maximum of 8 electrons The 3rd shell (M) has a maximum of 18 electrons The 4th shell (N) has a maximum of 32 electrons Our knowledge about the structure of atoms depends on the mathematical formulations predicted by Neils Bohr. He suggested that electrons are distributed in orbits and the number of electrons held in the orbit depends on the number of the orbit. The orbits are counted outwards from the nucleus. Higher the orbit number, the further the electrons are in that orbit from the nucleus. If the orbit number is “n”, then the maximum electrons held in the orbit is given as 2n2. The first orbit has n=1 and will hold a maximum of two electrons, the second orbit has n=2 and is capable of holding a total of eight electrons; similarly, the third orbit will be able to contain 18 electrons and so on. This is known as Pauli’s exclusion principle. Electrons within an atom have definite energies. The electrons closest to the nucleus (n=1) are most tightly bound; the reason is that of the stronger electrostatic attraction with the nucleus. Electrons in the highest orbit are least tightly bound. 1-8 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory The atomic structure of helium and neon Electron shell (orbit) designation 1-9 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Subshells Shells also have subshells. The subshells define the energy Ionisation levels. When the atom loses electrons or gains electrons in this process of electron exchange, it is said to be ionised. For ionisation to ‘s, p, d, f’ are the names given to the subshells that hold the take place, there must be a transfer of energy which results in a electrons in the shells of atoms. These orbitals have different change in the internal energy of the atom. An atom having more shapes (e.g. electron density distributions) and energies (e.g. 1s than its normal number of electrons acquires a negative charge is lower energy than 2s which is lower energy than 3s; 2s is and is called a negative ion (or ‘anion’). The atom that gives up lower energy than 2p). some of its normal electrons is left with less negative charges than positive charges and is called a positive ion (or ‘cation’). Physicists and chemists use a standard notation to indicate the Thus, ionisation is the process by which an atom loses or gains electron configurations of atoms. The notation consists of a electrons. sequence of atomic orbital labels (e.g. for phosphorus the sequence 1s, 2s, 2p, 3s, 3p) with the number of electrons Cation – A cation is a positively charged ion. Metals assigned to each orbital (or set of orbitals sharing the same typically form cations. label) placed as a superscript. Anion – An anion is a negatively charged ion. Non- metals typically form anions. For example, hydrogen has one electron in the s-orbital of the first shell, so its configuration is written 1s1. Lithium has two Examples of electron arrangements electrons in the 1s-subshell and one in the (higher-energy) The diagrams below show some examples of electron 2s-subshell, so its configuration is written 1s2 2s1 (pronounced arrangements in the shells of the respective atoms. Subshells “one-s-two, two-s-one”). Phosphorus (atomic number 15) is as are not shown. follows: 1s2 2s2 2p6 3s2 3p3. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used, since all but the last few subshells are identical to those of one or another of the noble gases. Phosphorus, for instance, differs from neon (1s2 2s2 2p6) only by the presence of a third shell. Thus, the electron configuration of neon is pulled out, and phosphorus is written as follows: [Ne] 3s2 3p3. This convention is useful as it is the electrons in the outermost shell that most determine the chemistry of the element. 1-10 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024  Module 3.1 Electron theory On period 1 On period 3 Electron arrangement of hydrogen and helium Electron arrangement of sodium, chlorine and argon On period 4 On period 2 Electron arrangement of lithium, carbon and neon Electron arrangement of potassium and calcium 1-11 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Valency Hydrogen is the simplest element. It has one electron. Its outer Now to oxygen and sulphur. Both have six outer electrons. Six shell only holds two electrons. Let us use hydrogen as a is two short of a full shell. Their normal valences are 2 and they standard to see how other atoms combine with it. The table combine with two atoms of hydrogen. below lists the simplest compound of selected elements with hydrogen. Finally, fluorine and chlorine – seven outer electrons. This is one short of a full shell. They both combine with a single Valency can be simply defined as the number of hydrogen hydrogen atom and their normal valences are 1. atoms that an element can combine with. In the table, helium, neon and argon have a valency of 0. They do not normally form As a side note, chlorine can also have valences of 3, 5 and 7. compounds. The reasons are well beyond the scope of these notes. Lithium, sodium and potassium have a valency of 1 because The rules above can be summarised as follows: they combine with one hydrogen atom. Beryllium, magnesium and calcium all have a valency of 2: they combine with two The normal valency of an atom is equal to the number of hydrogen atoms. Note that the valences of all these atoms are outer electrons if that number is four or less. Otherwise, equal to the number of outer electrons that these elements the valency is equal to eight minus the number of outer have. electrons. Boron and aluminium combine with three hydrogen atoms – The atoms with full electron shells (helium, neon, argon) are their valences are 3 – and they have three outer electrons. chemically inert forming few compounds. The atoms don’t even interact with each other very much. These elements are gases Carbon and silicon combine with four hydrogen atoms. The with very low boiling points. valency of these elements is 4. It will come as no surprise that they both have four outer electrons. Any element with four electrons in its outer shell is known as a semiconductor. What about nitrogen and phosphorus? They have five outer electrons. But they normally only combine with three hydrogen atoms. Their valences are 3. Note that three is five less than eight. These atoms are three electrons short of a full shell. Please note that both nitrogen and phosphorus can also have a valency of 5. Some atoms are capable of having more than one valence. That will confuse the issue, so we will talk about normal valency. 1-12 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory The atoms with a single outer electron or a single missing electron are all highly reactive. Sodium is more reactive than magnesium. Chlorine is more reactive than oxygen. Generally speaking, the closer an atom is to having a full electron shell, the more reactive it is. Atoms with one outer electron are more reactive than those with two outer electrons, etc. Atoms that are one electron short of a full shell are more reactive than those that are two short. Atoms with only a few electrons in its outer shell are good electrical conductors. Atoms with eight or close to eight electrons in their outer shells are poor conductors (or good insulators). This is why atoms with four electrons in its outer shell are semiconductors. Electrons in outer shells of some common elements 1-13 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory When a semiconductor (such as silicon or germanium) atom bonds with another similar atom, it does so covalently. Each atom shares one electron with four neighbour atoms. Thus all its electrons are used up in what becomes a solid lattice of semiconductor atoms. The solid material has, therefore, no free electrons (and no holes for electrons to fit into). The following names are given to ions of the specific number of electron bindings (valence): 1 electron binding – monovalent 2 electron binding – divalent 3 electron binding – trivalent 4 electron binding – tetravalent 5 electron binding – pentavalent 6 electron binding – hexavalent 1-14 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory “THIS PAGE INTENTIONALLY LEFT BLANK” 1-15 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Energy levels Since an electron in an atom has both mass and motion, it This indicates that the electron will not accept a photon of contains two types of energy. By virtue of its motion, the energy unless it contains enough energy to elevate itself to one electron contains kinetic energy. Due to its position, it also of the higher energy levels. Heat energy and collisions with contains potential energy. The total energy contained by an other particles can also cause the electron to jump orbits. electron (kinetic plus potential) is the factor which determines the radius of the electron orbit. In order for an electron to remain Once the electron has been elevated to an energy level higher in this orbit, it must neither gain nor lose energy. than the lowest possible energy level, the atom is said to be in an excited state. It is well known that light is a form of energy, but the physical form in which this energy exists is not known The electron will not remain in this excited condition for more than a fraction of a second before it will radiate the excess One accepted theory proposes the existence of light as tiny energy and return to a lower energy orbit. To illustrate this packets of energy called photons. Photons can contain various principle, assume that a normal electron has just received a quantities of energy. The amount depends upon the colour of photon of energy sufficient to raise it from the first to the third the light involved. Should a photon of sufficient energy collide energy level. In a short period of time, the electron may jump with an orbital electron, the electron will absorb the photon's back to the first level emitting a new photon identical to the one energy, as shown in the figure below. The electron, which now it received. has a greater than normal amount of energy, will jump to a new orbit farther from the nucleus. The first new orbit to which the A second alternative would be for the electron to return to the electron can jump has a radius four times as large as the radius lower level in two jumps; from the third to the second, and then of the original orbit. Had the electron received a greater amount from the second to the first. In this case, the electron would emit of energy, the next possible orbit to which it could jump would two photons, one for each jump. Each of these photons would have a radius nine times the original. Thus, each orbit may be have less energy than the original photon which excited the considered to represent one of a large number of energy levels electron. that the electron may attain. It must be emphasised that the electron cannot jump to just any orbit. The electron will remain This principle is used in the fluorescent light where ultraviolet in its lowest orbit until a sufficient amount of energy is available, light photons, which are not visible to the human eye, bombard at which time the electron will accept the energy and jump to a phosphor coating on the inside of a glass tube. The phosphor one of a series of permissible orbits. An electron cannot exist electrons, in returning to their normal orbits, emit photons of in the space between energy levels. light that are visible. By using the proper chemicals for the phosphor coating, any colour of light may be obtained, including white. 1-16 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Energy levels in an atom 1-17 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory This same principle is also used in lighting up the screen of a television picture tube. The basic principles just developed apply equally well to the atoms of more complex elements. In atoms containing two or more electrons, the electrons interact with each other and the exact path of any single electron is very difficult to predict. However, each electron lies in a specific energy band and the orbits will be considered as an average of the electron's position. 1-18 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory “THIS PAGE INTENTIONALLY LEFT BLANK” 1-19 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Elements, ions and compounds There are only two classes of pure substances, namely elements and compounds. To understand the difference between the two, look at the two diagrams below. Elements Elements are pure substances made up of atoms with the same number of protons. An element is a material that is made up of atoms of only one kind. Note that an element: consists of indivisible, minute particles called atoms; consists of only one kind of atom, all atoms of a given element are identical; cannot be broken down into a simpler type of matter by either physical or chemical means; can exist as either atoms (e.g. argon) or molecules (e.g. nitrogen); atoms of different elements have different masses; and is identified by the number of protons in its nucleus - the number of neutrons may change (isotopes) and/or the number of electrons may change (ions) but the element will retain its identity. 1-20 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory An element consists of atoms that are all the same kind A compound consists of two or more kinds of atoms in a fixed ratio. 1-21 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Compounds A compound is a material that is made up of two or more kinds of atoms that are chemically bonded together. The properties of a compound are different from the atoms that make it up. Chemical synthesis is the name given to the purposeful execution of chemical reactions to obtain a compound. Compounds can only be broken down chemically (i.e. by a chemical reaction). The splitting of a compound into its constituent elements is called chemical analysis, decomposition or breakdown. Note that a compound: consists of atoms of two or more different elements bound together chemically; can be broken down into a simpler type of matter (elements) by chemical means (but not by physical means); has properties that are different from its component elements; and always contains the same ratio of its component atoms. There are at least 118 elements in our known universe. They can form compounds by bonding in millions of different combinations − far too many to discuss here. 1-22 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Atoms of an Molecules of an Molecules of a Mixture of elements element element compound and a compound 1-23 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory “THIS PAGE INTENTIONALLY LEFT BLANK” 1-24 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory A water molecule representation (oxygen and hydrogen) Chemical symbol H2O The white, grey, and red spheres represent atoms of hydrogen, carbon, and oxygen, respectively. Oxygen (O2) Ethanol (C2H6O) Water (H2O) Ethanol glycol ((CH2OH)2) Carbon dioxide (CO2) Aspirin (C9H8O4) 1-25 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Example The compound with the formula H2O2 also consists of hydrogen atoms and oxygen atoms. The formula tells us that one molecule of this substance is made up of two atoms of hydrogen and two atoms of oxygen. Is H2O2 the same as water? No. Do not confuse H2O2 with H2O. H2O2 is a compound called hydrogen peroxide. Hydrogen peroxide is similar to water in that it is a clear, colourless liquid at room temperature (25°C) though more viscous, it is different in many ways. The following properties of hydrogen peroxide may convince you that it is not the same as water. Hydrogen peroxide has a boiling point of 150°C and it is a very effective bleach for clothes and hair. Concentrated hydrogen peroxide is so reactive that it is used as a component in rocket fuel. Hydrogen peroxide is extremely corrosive. We can drink water, but hydrogen peroxide is very hazardous and harmful. Even though they are made up of exactly the same elements, the two compounds are very different and should never be confused with one another. The purpose of the comparison of hydrogen peroxide and water above was to show you that the atoms in a given compound are always combined in a fixed ratio. In all water molecules in the universe, there will always be one O atom and two H atoms bonded together. 1-26 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory “THIS PAGE INTENTIONALLY LEFT BLANK” 1-27 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Conductors, semiconductors and non-conductors Conductors (insulators) In a conductor, electric current can flow freely, in an insulator it cannot. Metals such as copper typify conductors, while most non-metallic solids are said to be good insulators, having extremely high resistance to the flow of electrical charge through them. ‘Conductor’ implies that the outer electrons of the atoms are loosely bound and free to move through the material. Most atoms hold on to their electrons tightly and are insulators. In copper, the valence electrons are essentially free and strongly repel each other. Any external influence which moves one of them will cause a repulsion of other electrons which propagates, similar to a cascade of dominos, through the conductor. Simply stated, most metals are good electrical conductors, most non-metals are not. Metals are also generally good heat conductors while non-metals are not. Insulators Most solid materials are classified as insulators because they offer very large resistance to the flow of electric current. Metals are classified as conductors because their outer electrons are not tightly bound, but in most materials, even the outermost electrons are so tightly bound that there is essentially zero electron flow through them with ordinary voltages. Some materials are particularly good insulators and can be characterised by their high resistivities 1-28 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory An electrical wire has both a conductor material and an insulating material Ceramic insulators are commonly used in electrical pylons 1-29 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Semiconductors Solid materials are classified by the way the atoms are arranged within the solid. Materials in which atoms are placed at random are called amorphous. Materials in which atoms are placed in a highly ordered structure are called crystalline. Semiconductors are crystalline or amorphous solids with distinct electrical characteristics. They are of high resistance – higher than typical resistance materials, but still of much lower resistance than insulators. Their resistance decreases as their temperature increases, which is a behaviour opposite to that of a metal. Pure semiconductors have only a small number of free electrons available and pass a limited amount of electrical current. In general, their valence electrons are tightly bound within their crystal (lattice) structure. Semiconductors are extremely important in modern electronics because they can be used to control the amount of current in an electrical system. Their conducting properties may be altered in useful ways by the deliberate, controlled introduction of impurities (called ‘doping’) into the crystal structure, which lowers its resistance but also permits the creation of semiconductor junctions between differently-doped regions of the extrinsic semiconductor crystal. Although some pure elements and many compounds display semiconductor properties, silicon, germanium, and compounds of gallium are the most widely used in electronic devices. All these elements have four electrons in their outer shell (tetravalent). 1-30 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Semiconductor crystal materials and light emitting diodes (LEDs), in which semiconductor materials are used in their construction and operation Each atom in a silicon lattice has its valence electrons tightly bound within the lattice structure. Doping with impurities can create specific amounts of holes and free electrons, thus controlling the conductivity 1-31 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Summary Electrons per shell 1-32 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory Electrons per shell 1-33 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024 Module 3.1 Electron theory “THIS PAGE INTENTIONALLY LEFT BLANK” 1-34 Copyright 2024 © Joramco Academy FOR TRAINING PURPOSE ONLY Issue 2 – June 2024