Electron Essays & Research Papers

Best Electron Essays

  • The Discovery of the Electron - 522 Words
    The Discovery Of The Electron The electron was discovered in 1895 by J.J. Thomson in the form of cathode rays, and was the first elementary particle to be identified. The electron is the lightest known particle which possesses an electric charge. Its rest mass is Me 9.1 x 10 -28 g, about 1/1836 of the mass of the proton or neutron. The charge of the electron is -e = -4.8 x 10^-10 esu
    522 Words | 2 Pages
  • Electron Microscope - 275 Words
    The electron microscope, instrument that produced the first magnified image showing ‘three-dimensional' and highly magnified image of a small object. It directs a beam of electrons rather than light through a specimen. The beam of electrons is created from an electron gun. This beam then travels through the length of the microscope cylinder, which contains the lenses, the specimen chamber, and the image-recording system. Two types of electron lenses are used, electrostatic and...
    275 Words | 1 Page
  • Electron Microscope - 730 Words
    An electron microscope is a type of microscope that produces an electronically-magnified image of a specimen for detailed observation. The electron microscope (EM) uses a particle beam of electrons to illuminate the specimen and create a magnified image of it. The microscope has a greater resolving power than a light-powered optical microscope, because it uses electrons that have wavelengths about 100,000 times shorter than visible light (photons), and can achieve magnifications of up to...
    730 Words | 2 Pages
  • Electron Configuration - 266 Words
    In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals.[1] For example, the electron configuration of the neon atom is 1s2 2s2 2p6. Electronic configurations describe electrons as each moving independently in an orbital, in an average field created by all other orbitals. Mathematically, configurations are described by Slater determinants or configuration state...
    266 Words | 1 Page
  • All Electron Essays

  • Electron Microscopy - 1479 Words
    Introduction to Electron Microscopy Prof. David Muller, dm24@cornell.edu Rm 274 Clark Hall, 255-4065 Ernst Ruska and Max Knoll built the first electron microscope in 1931 (Nobel Prize to Ruska in 1986) T4 Bacteriophage Electron Microscopy bridges the 1 nm – 1 μm gap David Muller 2008 between x-ray diffraction and optical microscopy Tools of the Trade AFM MFM Scanned Probe Microscope (includes Atomic Force Microscope) Transmission Electron Microscope Scanning...
    1,479 Words | 13 Pages
  • Electron and Points - 261 Words
    Insert completed data tables for each part of the lab. Be sure that the data tables are organized and include units when necessary. 1. Melting Point (4 points) 2. Conductivity (4 points) Part II: Conclusion Answer the following questions in your own words, using complete sentences. 1. Based on your observations in the lab, categorize each unidentified compound as ionic or covalent. Explain in one or two sentences why you categorized the compounds the way that you did. (5 points)...
    261 Words | 2 Pages
  • Electron Microscopy - 558 Words
    Electron Microscopy The electron microscope is a very powerful microscope which can see things that normal microscopes cannot. There are 2 types of electron microscope: the transmission electron microscope and the scanning electron microscope. The sample must be in a vacuum so that no air bubbles are on the produced image and also because the electrons are absorbed by the molecules in the air, this means that the electron microscope cannot be used to look at living cells. The tissue is soaked...
    558 Words | 2 Pages
  • Atom and Electrons - 1371 Words
    SECTION A Mark your answers in the answer sheet provided. (NA = 6.022 x 1023) 1. Which one of the following is an example of a physical property? A) dynamite explodes D) ice floats on top of liquid water B) meat rots if it is not refrigerated E) a silver platter tarnishes C) gasoline burns 2. Which one of the following represents a physical change? A) water, when heated to 100°C, forms steam B) bleach turns hair yellow C) sugar, when heated, becomes brown...
    1,371 Words | 6 Pages
  • electron microscopy - 6551 Words
     Paper submission on electron microscopy professor: Ernesto Suarez by ananthalakshmi adapa University of Hartford What is a electron microscopy? An electron microscope (EM) is a type of microscope that uses an electron beam to illuminate a specimen and produce a magnified image. An EM has greater resolving power than a light microscope and can reveal the structure of smaller objects because...
    6,551 Words | 19 Pages
  • Free Electron Theory - 1890 Words
    FREE ELECTRON THEORY Classical free electron theory of metals This theory was developed by Drude and Lorentz and hence is also known as Drude-Lorentz theory. According to this theory, a metal consists of electrons which are free to move about in the crystal like molecules of a gas in a container. Mutual repulsion between electrons is ignored and hence potential energy is taken as zero. Therefore the total energy of the electron is equal to its kinetic energy. Drift velocity If no...
    1,890 Words | 7 Pages
  • Single Electron Transistor - 2248 Words
    SINGLE ELECTRON TRANSISTOR SEMINAR ABSTRACT A single-electron transistor consists of a small conducting island connected to the source and drain leads by tunnel junctions and connected to one or more gates. The nanometre scale conductive island is embedded in an insulating material. Gate signals are capacitive coupled to the island. Two gate signals can be applied to the island out of which one is optional. Here, only one electron can tunnel from source to drain. The...
    2,248 Words | 9 Pages
  • Electrons in Atoms Outline - 590 Words
    Chapter 5: Electrons In Atoms A. Models of the atom i. The Development of Atomic Models Protons and neutrons make up a nucleus surrounded by electrons Rutherford’s model or theory ( figured electrons move around the nucleus) His theory didn’t explain why metals or compounds of medals give off characteristics of colors when heated. Also didn’t explain why the atomic model could not explain the chemical properties of elements ii. The Bhor Model Bohr proposed that an electron is found in...
    590 Words | 2 Pages
  • Calibration of photon and electron beams
    JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 1, NUMBER 3, SUMMER 2000 Comparison between TG-51 and TG-21: Calibration of photon and electron beams in water using cylindrical chambers S. H. Cho,a) J. R. Lowenstein,b) P. A. Balter,c) N. H. Wells,d) and W. F. Hansone) Department of Radiation Physics, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Box 547, Houston, Texas 77030 ͑Received 31 March 2000; accepted for publication 8 June 2000͒ A new...
    3,784 Words | 22 Pages
  • The Electron of Atomic Physics - 610 Words
    Sir J.J.THOMSOM is to physics what electron is to an atom. He charged the world of physics with his discoveries and gave momentum to atomic physics. Physics is what today because of this British scientist who is regarded as the greatest experimental physicists of this century. A bookseller’s son, Thomsom studied at the Owens College and later at the Manchester University. He wanted to become an engineer, but his father’s death in 1872 forced him to study Mathematics, Physics and Chemistry as...
    610 Words | 3 Pages
  • Atom and Proton Electron - 896 Words
    Chem 170 Exam 2 Review Chapters 5, 11-13 Instructions: You are allowed to use a scientific calculator to perform mathematical operations. Please silence and put away all cell phones and pagers! Part I. This section is multiple-choice. Fill in the letter corresponding to the best answer on your Scantron form #882. 1. The __________ and __________ contribute most to the mass of an atom, while the _____________ determines the atom’s chemical behavior. A. B. C. D. E. proton, neutron, electron...
    896 Words | 4 Pages
  • Electron and Potential Difference - 520 Words
    HOMEWORK PROBLEMS Chapter 27: CAPACITANCE AND DIELECTRICS Show the equations and calculations, and box your answer. Be sure to include the units. NOTE: Any four questions from this HW will be graded, and the marks for this HW will be based on these only. (1, 2, 3, 12, 13, 18, 19, 21, 22, 29, 31, 32, 44) 1. A proton beam in an accelerator carries a current of 125 A. If the beam is incident on a target, how many protons strike the target in a period of 23.0 s? 2. A copper wire has a...
    520 Words | 2 Pages
  • Atom and Valence Electrons - 6071 Words
    ------------------------------------------------- 1.Top of Form Arrange the following elements in order of increasing electronegativity: germanium, bromine, selenium, arsenic Please answer this question according to the general rules you have learned regarding periodic trends. DO NOT base your answer on tabulated values since exceptions may occur. | germanium smallest arsenic selenium bromine largest Feedback: Electronegativity is the ability of an atom in a molecule to attract...
    6,071 Words | 32 Pages
  • Charge to Mass Ratio of the Electron
    Charge to Mass Ratio of the Electron Thomas Markovich and John Mazzou Departments of Physics University of Houston Houston, TX 77204-5006 (Dated: September 23, 2010) We sought to reproduce the experiment first preformed by KT Bainbridge to determine the charge to mass ratio of the electron. In this paper, we derived the relationship between this ratio and measurable quantities, detailed our experimental setup, with in depth and specific circuit diagrams. We determined the mass to charge ratio to...
    2,489 Words | 10 Pages
  • Resolution and Magnification with an Electron Microscope
    Notes for WK2 – 10 September Lesson 1 * State the resolution and magnification that can be achieved by an electron microscope. * explain the need for staining samples for use in electron microscopy Lesson 2 * calculate linear magnification of an image such as photomicrograph or electron micrograph Key words * Resolution= the ability to distinguish 2 separate points as distinct from each other. * Magnification= the number of times greater an image is than the actual object...
    1,015 Words | 4 Pages
  • Gizmo: Atom and Valence Electrons
    Name: ______________________________________ Date: ________________________ Student Exploration: Covalent Bonds Vocabulary: covalent bond, diatomic molecule, Lewis diagram, molecule, noble gases, nonmetal, octet rule, shell, valence, valence electron Prior Knowledge Questions (Do these BEFORE using the Gizmo.) 1. There are eight markers in a full set, but Flora and Frank each only have seven markers. Flora is missing the red marker, and Frank is missing the blue marker....
    940 Words | 7 Pages
  • Charge on Electron Lab - 461 Words
    Charge of an Electron Lab Purpose and Introduction: ​The purpose of this lab was to determine the number of zinc atoms plated on one electrode and to determine the charge of one atom of zinc. This was to determine the charge carried by one electron. The use of electrons is in everyday life. For example, using electrons in electroplating. That is the process of covering one metal (usually a cheaper metal) with another using an electric current. The current dissolves the one metal by...
    461 Words | 2 Pages
  • Report On Deflection Of An Electron Beam
    Laboratory I: Problems 4 and 5 Deflection of an Electron Beam by an Electric Field and Deflection of an Electron Beam and Velocity By: John Greavu Partners: Shane Ruff, Hannah Eshenaur, & David Sturg Professor: John Capriotti TA: Barun Dhar July 19, 2013 OBJECTIVE: The objective of this lab was to scientifically determine the deflection of an electron from its original path due to its passing through an electric field as a function of the electric field strength (problem 4), as well as its...
    1,614 Words | 8 Pages
  • Tutorial: Atom and Electron Affinity
    DIVISION OF CHEMISTRY :MODULE: GENERAL CHEMISTRY (CHY2021) TUTORIAL # 2 DATE: September 2013 1. Define the following terms: mass number, atomic number and the atomic mass unit (amu). 2. With the help of The Periodic Table, complete the table below. Symbol Atomic # Proton # Neutron # # of Electrons Mass Number Charge Ar 19 31 17 18 35 20 18 3+ 40 3. In your own words, explain Thomson’s and Rutherford’s contribution to the atomic theory. Give sketches to substantiate your answer. 4....
    891 Words | 3 Pages
  • Introduction to Scanning Electron Microscopy
    Introduction To Scanning Electron Microscopy At the completion of the prac, the practical experience of operating a scanning electron microscope is sufficient to operate the particular machine in the future. During the experiment, two different gold plated samples are analysed under the SEM and compositional and topographic information is identified and analysed. Both the information is derived by changing the working distance, accelerating voltage, aperture size, probe current, resolution...
    3,454 Words | 11 Pages
  • Electromagnetic Radiation and Valence Electrons
    Introductory Chemistry, 2e (Tro) Chapter 9 – Electrons in Atoms and the Periodic Table True/False Questions 1) When the elements are arranged in order of increasing number of protons, certain sets of properties recur periodically. 5) A particle of light is called a packet. 9) Ultraviolet light produces suntans and sunburns. 13) Electrons behave like particles and we can describe their exact paths. 17) The ground state is when an electron in an atom is excited into the lowest possible vacant...
    517 Words | 2 Pages
  • J.J. Thomson – Discovery of the Electron
    CHE003 Chemistry Individual Assignment J.J. Thomson – Discovery of the electron Table of Contents Introduction 2 Biographical information 3 Background information 4 Experimental information 5 Impact 6 Conclusion 7 J.J. Thomson – Discovery of the electron Introduction The discovery of the electron is affirmative and justly credited to the English physicist Sir Joseph John Thomson (Weinberg, 2003). He had found and identified the electron in Cavendish Laboratory,...
    1,489 Words | 5 Pages
  • Electrons: Electric Charge - 526 Words
    The electron is a fundamental subatomic particle that carries a negative electric charge. It is a spin-½ lepton that participates in electromagnetic interactions, and its mass is less than one thousandth of that of the smallest atom. Its electric charge is defined by convention to be negative, with a value of −1 in atomic units. Together with atomic nuclei, electrons make up atoms; their interaction with adjacent nuclei is the main cause of chemical bonding. The name "electron" comes...
    526 Words | 2 Pages
  • 0304 Valence Electrons And Bonding Individual
    03.04 Valence Electrons and Bonding Individual neutral atoms are rarely found in nature. The noble gases are the only elements that are found as single atoms more often than they are found in compounds. Atoms are held together in compounds by electrostatic attraction between positive nuclei and negative electrons. This attraction holds atoms together in a chemical bond, a link between two atoms resulting from the mutual attraction of their nuclei for valence electrons. All chemical bonds...
    484 Words | 2 Pages
  • Physics Electron Gun Magnetic Field
    October 30, 2014 Jordan Hollenbeck Juhn Borruel Electron Gun - Effects of a Magnetic Field Purpose: The objective of this experiment is to study the motion of an electron in a magnetic field and to establish (show/verify) a relationship between the magnetic strength and the distance the electrons are deflected. Theory and Procedure: The electron gun is an instrument that consists of an electron source (which emits electrons and focus the stream into a beam), a magnetic coil (which uses a...
    900 Words | 12 Pages
  • Deflection of an Electron Beam by a Magentic Field
    Deflection of an Electron Beam by an Electric Field Nicole N Lab Problem 1.4 – February 3, 2011 Problem Statement: We were asked to test the design of an electron microscope to determine how a change in the electric field affects the position of the beam spot. The goal is to find out how different variables, such as charge of the deflection plates providing a vertical electric field and initial velocity of the electron beam will affect the amount of deflection the electron beam...
    1,154 Words | 4 Pages
  • Writing Lewis Electron Dot Structure
     Writing Lewis Dot Formula November 8, 2013 I. Learning Objectives At the end of the sessions, the students of III- 15, and III – 10 must be able to: 1. Students will be able to interpret and draw Lewis dot diagrams for individual atoms and both covalent and ionic compounds. II. Subject Matter A. Topic: Chemical Bonding B. References 1. Department of Education, Culture and Sports. (1991). Science and Technology III. Quezon City: Book Media Press, pp. 273. 2. Estrella, Mendoza E....
    415 Words | 2 Pages
  • Comparison Between Light and Electron Microscope
    The introduction of the microscope as a tool for the biologist brought about a complete reappraisal of the micro- composition of biological tissues, organisms and cells. In the infancy of its application to organic materials, it was the implement of anatomists and histologists in particular, where previously unimagined structures in cells were revealed. More recent developments in biological specimen preparation have come from biochemists and physicists who have used the microscope to examine...
    2,137 Words | 6 Pages
  • Compare and Contrast the Use of Light and Electron Microscopes in Biological Studies.
    Compare and contrast the use of light and electron microscopes in biological studies. Microscopes are laboratory equipment which are used to observe any matter that is too small to be seen by the naked eye. There are several types of microscopes – the two most common being the optical microscope, also known as a light microscope, and the electron microscope, which can be either a transmission electron microscope (TEM) or a scanning electron microscope (SEM). There are more differences than...
    1,020 Words | 3 Pages
  • lab report - 763 Words
    Chemical Bonds Lab Report Objective & Introduction: The objective of this experiment was to find more about metallic, ionic, and covalent compounds. To test this you will be checking the melting point, solubility, and conductivity of various substances. A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements. The solubility, melting point, and conductivity are all physical properties that could help you determine what type of...
    763 Words | 6 Pages
  • autobiography - 863 Words
    Millikan Oil Drop Experiment Purpose The purpose for this lab is to find the terminal velocity, mass, and radius of the oil drops to find the charge of an electron. Hypothesis The prediction for this investigation is that an oil drop entering the space between two plates would be affected by the uniform electric, gravitational field and the viscous drag. The oil drops would reach terminal velocity without applying any voltage. So the mass of the oil drop, radius and from the radius the...
    863 Words | 4 Pages
  • Gunshot Residue Aanalysis - 1614 Words
    Forensic Chemistry - CH6058 Gunshot Residue Analysis (GSR) When a firearm is discharged, residues from the bullet’s force, the primer, cartridge case, firearm itself and the powder from the propellant are expelled from gaps in the guns working parts (Pepper, 2005: 118). These particles are known as gunshot residue (GSR) or firearm discharge residue (FDR) and are composed of partially burnt and un-burnt propellant powder, particles from the ammunition primer, smoke, lubricants, grease and...
    1,614 Words | 5 Pages
  • formal lab report on ionic and covalent compounds
    Formal paper number 1 Professor Tolentino Maria Oyervide EXPERIMENT #4 IONIC AND COVALENT COMPOUNDS Abstract: This experiment was divided in four steps to find the electrical conductivity of covalent and ionic solutions. There were four unknown solutes A, B and C. Each had a specific weight and was dissolved in a certain amount of solute to form either the covalent or ionic solution. Covalent compounds are made up of molecules which are electrically neutral. Ionic compounds are...
    423 Words | 2 Pages
  • Physics Final Exam Version 2c 2
    Physics Final Exam revision c 4/8/15 Directions: It is important that you provide answers in your own words. Please focus only on information from the text/eBook to create your own solutions. Please do not use direct information from an outside source (especially copying and pasting from an “answer” website). Use of direct information from an outside source is against school policy. All answers will be checked for plagiarism. Instances of plagiarism can result in probation or...
    1,084 Words | 4 Pages
  • wave packets - 8275 Words
    Dynamics of electron packets and photocounts Vladimir Bykov* and Valentin Turin** *General Physics Institute, Russian Academy of Sciences, ul. Vaviova 38, Moscow, 1 17942 Russia, v.p.bykov@mtu-net.ru **Moscow Institute ofPhysics and Technology, voturin@pop3.mipt.rn ABSTRACT An alternative approach to the theory ofphotocounts is discussed. Mechanism of sharpening of electronic distribution at the expansion of many-electron packets is investigated. Arising of such inhomogeneities...
    8,275 Words | 55 Pages
  • Theory of Rlelativity - 370 Words
    1) Annual energy consumption in the United States (Q24; Giancoli Chap 26) The total annual energy consumption in the United States is about 8 10 J. 19 How much mass would have to be converted to energy to fuel this need? 2) The nearest star to Earth (Q49; Giancoli Chap 26) The nearest star to Earth is Proxima Centauri, 4.3 light-years away. (a) At what constant velocity must a spacecraft travel from Earth if it is to reach the star in 4.0 years, as measured by travellers on the spacecraft?...
    370 Words | 2 Pages
  • Stm Tips - 688 Words
    Background Research Scanning Tunneling Microscope; or STM, allows scientists to image or display crystalline material surfaces down to an atomic level. Basically; it shows the formation of surface atoms on conducting and semi-conducting materials such as metals, or metalloids. First invented by Gerd Binnig and Heinrich Rohrer in 1981; the Scanning Tunneling Microscope used quantum tunneling to extract atomically resolved images to understand the morphology of crystalline surfaces including...
    688 Words | 2 Pages
  • Atomic Structure - 978 Words
    The Rutherford Model of the Atom 1. In 1911 Rutherford proposed the nuclear model of atomic structure. He suggested that an atom consists of a central nucleus (where most of the mass of the atom is concentrated) having a positive charge, surrounded by moving electrons carrying negative charge. Geiger and Marsden carried out an experiment to verify his proposal. The Geiger/Marsden a Particle Scattering Experiment 1. The apparatus is illustrated in the diagram below. | 2. The...
    978 Words | 4 Pages
  • Mass Spectrometer - 886 Words
    Mass Spectrometer When you hear the words mass spectrometer, what do you think of? To some people, these words do not have any meaning; however the mass spectrometer has a great significance. The mass spectrometer has been a universal research tool, mostly involved in comparing the masses of atoms. Since the invention of this tool about 100 years ago, the mass spectrometer has been responsible for the description of molecular structure, the detection of isotopes, the classification of...
    886 Words | 3 Pages
  • cyclotron - 1842 Words
    Cyclotron From Wikipedia, the free encyclopedia For other uses, see Cyclotron (disambiguation). A French cyclotron, produced in Zurich,Switzerland in 1937 A modern cyclotron for radiation therapy A cyclotron is a type of particle accelerator in which charged particles accelerate outwards from the center along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying (radio frequency) electric field. History[edit]...
    1,842 Words | 6 Pages
  • Foreign Scientists and Their Contribution in Chemistry
    Antoine Lavoisier was born in the year 1743 to a wealthy family and inherited a huge fortune at the age of five after the demise of his mother. A noble man by profession has contributed a lot in both chemical and biological science. Antoine Lavoisier is the first person to term Oxygen and Hydrogen and also was the first one to establish that sulphur is not a compound but an element. He was the first person to determine that air is a mixture of nitrogen and oxygen. His other contribution...
    580 Words | 2 Pages
  • Radiation - 1071 Words
    Answer: Radiation has a profound effect on matter. Particularly in forms where it has high energy. There are basically two kinds of radiation, and they are electromagnetic energy and particulate radiation. Low energy electromagnetic radiation isn't generally hazardous, as long as the field strengths are low. You wouldn't want to stand in front of a radar antenna when it's radiating, but we are swept by low power electromagnet energy all the time. Those so-called radio waves are everywhere....
    1,071 Words | 3 Pages
  • Relative Rates: Free-Radical Bromination
    BroIn this experiment of the relative rates of free-radical chain bromination, we were expected to be able to determine the relative reactivates of the many types of hydrogen atoms involved toward bromine atoms. Bromination is defined to be a regioselective reaction meaning bromine has preference of making or breaking a bond over all other directions that it may have had available. In this case, Markovnikov’s rule is revealed to be the case in this situation that states that adding a protic acid...
    582 Words | 2 Pages
  • Early Atomic theories - 658 Words
    Early Atomic Theories . Democritus 460 BC – 370 BC First to suggest existence of atoms based off intuition and reasons No experimental evidence found John Dalton 1766 – 1844 (Dalton’s Theory) Elements are made of extremely small particles called atoms. Atoms of given element are identical in size, mass, and other properties; atoms of different elements differ in size, mass, and other properties. Atoms cannot be subdivided, created, or destroyed. Atoms of different elements combine in...
    658 Words | 3 Pages
  • Atom Development with Scientists Involved
    Pineda, Carlitos Miguel Ponce M. January 9, 2013 AIT2A Natural Science 12 ATOM DEVELOPMENT WITH SCIENTISTS INVOLVED 400 B.C. - Democritus’ atomic theory posited that all matter is made up small indestructible units he called atoms. Democritus expanded the idea to state that matter was composed of small particles called "atoms" that could be divided no further. These atoms were all composed of the same primary matter with the only differences between them being their size,...
    1,100 Words | 4 Pages
  • Oled - 496 Words
    The OLED is a solid-state devices composed of thin films of organic molecules that create light with the application of electricity. To compare with LCD system, OLED is Thinner, Faster, More efficient, Wider, and more Flexible. actually, it will be a next generation display and the future's light source. So to get close with new technology, we started on research that. Main purpose is using organic materials to produce the Red, Green, and Blue OLED, and to improve the efficiency. For that we...
    496 Words | 2 Pages
  • Robert Andrew Millikan - 569 Words
    Robert Andrew Millikan In 1909 Robert Andrew Millikan set up an apparatus to measure the charge of an electron within an accuracy range of 3%. In 1913 he came out with a value of the electrical charge that would serve the world of science for a generation. Young Millikan had a childhood like most others: he had no idea what his profession would be. Once he recalled trying to jump from a rowboat to a dock, falling in the water, and almost drowning. Here he had his first account with...
    569 Words | 2 Pages
  • lab reports - 934 Words
    CHM 3411 – Problem Set 6 Due date: Wednesday, March 23rd. Do all of the following problems. Show your work. 1) Consider the cyclic molecule C8H8, the eight carbon analogue to benzene. a) Write the secular detrerminant corresponding to the pi-bonding in C8H8. b) Using the secular determinant, the following energies are found for the pi-bonding molecular orbitals: 1 =  + 2 2 =  + 1.41 (two states) 3 =  (two states) 4 =  - 1.41 (two states) 5 =  - 2 Give the...
    934 Words | 5 Pages
  • Radiation - 693 Words
    Radioactivity computer research: Instructions and Questions [Note: Links to Bitesize websites may direct you to a ‘home’ page for Radiation and the Universe- click ‘Activity’ for Radioactive Substances and scroll through until you find the appropriate page] 1) Go to http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/radiation/radiocativerev1.shtml . What is an isotope? How many isotopes of hydrogen are there? An isotope is an atoms which are from the same element but have different...
    693 Words | 2 Pages
  • Development of an ultra-thin film comprised of a graphene membrane and carbon nanotube vein support
    ARTICLE Received 26 Jul 2013 | Accepted 13 Nov 2013 | Published 20 Dec 2013 DOI: 10.1038/ncomms3920 Development of an ultra-thin film comprised of a graphene membrane and carbon nanotube vein support Xiaoyang Lin1,2, Peng Liu1,2, Yang Wei1,2, Qunqing Li1,2, Jiaping Wang1,2, Yang Wu1,2, Chen Feng1,2, Lina Zhang1,2, Shoushan Fan1,2 & Kaili Jiang1,2 Graphene, exhibiting superior mechanical, thermal, optical and electronic properties, has attracted great interest. Considering it being...
    4,959 Words | 26 Pages
  • Video Report Video “Nanospace: a Voyage Into Ultra-Microscopic Worlds – Part 1: the Atom Revealed”
    GEK1509: Introduction to the Nanoworld Short Project Report I Done by: Nguyen Huy Anh – A0088386L NUS Business School Nanoscience and nanotechnology is an area of science which study the behavior and manipulating objects on atomic or molecular scale. This is a relatively new area of science, which only emerged in the past 40 years, since Richard Feynman’s famous lecture “ There are plenty of rooms in the bottom” in 1959. This area surely brings many challenges, but at the same time opens...
    1,422 Words | 4 Pages
  • Lewis Structures - 468 Words
    A Brief Tutorial on Drawing Lewis Dot Structures (YouTube references at the end) Procedure for Neutral Molecules (CO2) 1. Decide how many valence (outer shell) electrons are posessed by each atom in the molecule. 2. If there is more than one atom type in the molecule, put the most metallic or least electronegative atom in the center. Recall that electronegativity decreases as atom moves further away from fluorine on the periodic chart. Arrangement of atoms in CO2: 3. Arrange...
    468 Words | 2 Pages
  • Dual Nature and Radiation of matter
    The Maxwell’s equations of electromagnetism and Hertz experiments on the generation and detection of electromagnetic waves in 1887 strongly established the wave nature of light. Towards the same period at the end of 19th century, experimental investigations on conduction of electricity (electric discharge) through gases at low pressure in a discharge tube led to many historic discoveries. The discovery of X-rays by Roentgen in 1895, and of electron by J. J. Thomson in 1897, were important...
    499 Words | 2 Pages
  • Lemon as Battery - 447 Words
    It is possible to get electricity from a lemon (and a few other acidic fruits and vegetables) using two strips of metal. The most readily available combination is copper and zinc. The zinc piece can be taken from the casing of an old carbon "D" cell (battery); some zinc coated nails may work as well. The copper can be a coin containing a high amount of copper. (Note: some recent copper coins, including the newer U.S. pennies, contain low amounts of copper mixed with zinc. If in doubt, use a pure...
    447 Words | 2 Pages
  • Lab Report Electrical Conductivity
    Lab Report Electrical Conductivity Introduction There are some substances that are capable of conducting electricity, and the reason they conduct electricity is because of the type of compound the substance is. Electrolytes or any ionic compound conduct electricity and nonelectrolytes do not conduct electricity. An Ionic compound is formed from the electrical attraction between anions and cations, typically a metal with a non-metal, except hydrogen. When an ionic compound forms, the...
    790 Words | 5 Pages
  • Rutherford's Atom Theory Explained
    Science Holiday Homework Aldo 10D The Rutherford’s Experiment and the Geiger Marsden experiment were both the same experiment, where Rutherford being the mentor of Geiger and Marsden in the investigation of the experiment at the University of Manchester in 1909. The experiment was so important because it changes our view and understanding upon the structure of the atom. Before Rutherford, there was a man named Joseph John Thomson who proposed the structure of the atom. He stated that the...
    895 Words | 3 Pages
  • Condense Matter Physics - 1235 Words
    ZHEJIANG UNIVERSITY Department of Physics Thermal Physics Problem Set #3, Solution Date: 2013/03/29 1. If we apply the highly successful kinetic theory of gases to a metal, consider as a gas of electrons (in fact, back in 1900 Drude constructed the theory, hence the Drude theory of metals), and assume that the electron velocity distribution is given by the Maxwell-Boltzmann distribution, what would the most probable speed, average speed, and rms speed for electrons at room...
    1,235 Words | 13 Pages
  • History of the Atom - 303 Words
    Jo Adrian P. del Mundo CN 08 3S (A) August 1, 2013 Atomic Models The Electron Cloud Model - an atom is comprised of a nucleus made up of neutrons and protons, and electrons moving extremely fast around the nucleus, forming an electron cloud instead of moving in orbits like what Bohr’s model suggests - proposed by Erwin Schrodinger in 1926, when he derived this model using a mathematical equation that he himself made...
    303 Words | 1 Page
  • ssss - 665 Words
    SLG Practice Final Exam Chem. 113 True and False 1. The Bohr Theory explains that an emission spectral line is due to an electron losing energy and changing orbitals. 2. 4s orbitals have higher energy than 3d orbitals. 3. An atom with an even number of electrons is always diamagnetic. 4. Covalent bonds are formed by atoms sharing electrons. Multiple Choice 5. Choose the INCORRECT statement about NH2-: a) There is one lone pair on N. b) There are two σ bonds. c) There are no...
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  • Device Fabrication: Development of a Nano-Contact Platform
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