Radioactivity Karolina H. Czarnecka, PhD Department of Molecular Bases of Medicine
|
|
- Christopher Harvey
- 6 years ago
- Views:
Transcription
1 Radioactivity Karolina H. Czarnecka, PhD Department of Molecular Bases of Medicine
2 The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number (number of protons in the nucleus), electron configurations, and recurring chemical properties.
3 NUCLEAR FORCE and Radioactivity For a given number of protons, it is efficient only when a certain number of neutrons are present: if they are too scarce or too numerous, the glue no longer functions and the nucleus disintegrates -> radioactive nucleus. Instable nucleus is changing into more stable radioactive decay
4 Stable nuclei and radioactive nuclei The phenomenon of radioactivity is associated with the transformation of a nucleus, which "wants" to change into something more stable. A radioactive nucleus will choose among the various possible modes of radioactivity, that or those which provide it with the fastest return to stability. Thus, the lifetime of a radioactive nucleus depends only on the ease with which it can mutate into a more stable form.
5 Stable nuclide nuclides that are not radioactive and do not spontaneously undergo radioactive decay. When such nuclides are referred to in relation to specific elements, they are usually termed stable isotopes. 80 elements have at least one stable isotope which is never observed to decay, amounting to a total of about 254 stable isotopes. Hydrogen-1 (protium) Hydrogen-2 (deuterium) Helium-3 Helium-4no mass number 5 Lithium-6 Lithium-7no mass number 8
6 Unstable nuclide nuclides that are radioactive and can spontaneously undergo radioactive decay. thousands of isotopes have been characterized as unstable. These "radioisotopes" decay over time scales ranging from fractions of a second to trillions of years. too few or too many neutrons (in relation to the number of protons) will cause it to decay beta decay a nitrogen-16 atom (7 protons, 9 neutrons) is converted to an oxygen-16 atom (8 protons, 8 neutrons)[19] within a few seconds of being created.
7 unstable nuclei emit alpha particles (He nuclei) and beta particles (electrons) heavy nuclei are unstable and `decay', meaning that they spontaneously split into smaller nuclei and emit stray particles. This is called radioactivity.
8 Nuclear transmutation coming back to alchemy and the search of Philosopher's stone is the proces of conversion of one chemical element or isotope into another through nuclear reactions (in which an outside particle reacts with a nucleus) f.ex. fusion through radioactive decay (where no outside particle is needed).
9 ISOTOPES For nearly all chemical elements, there are several combinations of protons and neutrons which provide stability to the atom's nucleus. The different isotopes of a given element have the same atomic number but different mass numbers since they have different numbers of neutrons.
10 ISOTOPES The chemical properties of the different isotopes of an element are identical, but they will often have great differences in nuclear stability. For stable isotopes of light elements, the number of neutrons will be almost equal to the number of protons, but a growing neutron excess is characteristic of stable heavy elements.
11 more than 99% of the nuclei of oxygen atoms have 8 protons and 8 neutrons in less than one percent of cases, the oxygen nuclei have 8 protons and either 9 or 10 neutrons These three possible combinations constitute the three stable isotopes of oxygen. All other combinations lead to an unstable isotope of oxygen, that is a radioactive oxygen nucleus.
12 The element tin (Sn) has the most stable isotopes with 10, the average being about 2.6 stable isotopes per element. tiny difference in the spectral frequencies of hydrogen and deuterium comes from an essentially mechanical source, the slight change in the "reduced mass" associated with the orbiting electron. But for practical purposes the chemical behavior of the isotopes of any element are identical.
13 In Nuclear physics the proces of transmutation of one elemnts into other is posssible in the process of bombing (targetitng) the Mercurium with neutrinos (n), deuter or
14 NUCLEAR POWER The neutron is essential to the production of nuclear power. neutrons were used to effect many different types of nuclear transmutations. In 1938 the discovery of nuclear fission led to the construction of atom bombs due to the nucelar chain reaction The fission event produce neutrons, each of these neutrons might cause further fission events
15 NUCLEAR FISSION is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts (lighter nuclei). The fission process often produces free neutrons and gamma photons, and releases a very large amount of energy even by the energetic standards of radioactive decay.
16 Fission is a form of nuclear transmutation because the resulting fragments are not the same element as the original atom. Most fissions are binary fissions (producing two charged fragments) The two nuclei produced are most often of comparable but slightly different sizes, typically with a mass ratio of products of about 3 to 2, for common fissile isotopes. In the liquid drop model, the two fission fragments are predicted to be the same size. The nuclear shell model allows for them to differ in size, as usually experimentally observed
17 NUCLEAR FISSION Simple method for producing radioactive nuclei consists in fragmenting stable nuclei into several pieces
18 EXCITED ATOMS Excitation is an elevation in energy level above an arbitrary baseline energy state. In quantum mechanics an excited state of a an atom / molecule / nucleus is any quantum state of the system that has a higher energy than the ground state (that is, more energy than the absolute minimum). The temperature of a group of particles is indicative of the level of excitation.
19 Atomic excitation hydrogen The ground state of the hydrogen atom corresponds to having the atom's single electron in the lowest possible orbit - "1s" ( which has the lowest possible quantum numbers). By giving the atom additional energy (for example, by the absorption of a photon of an appropriate energy), the electron is able to move into an excited state (one with one or more quantum numbers greater than the minimum possible). If the photon has too much energy, the electron will cease to be bound to the atom, and the atom will become ionised.
20 ATOMIC SPECTRA excited atoms emit light of certain wavelengths which correspond to different colors. The emitted light can be observed as a series of colored lines with dark spaces in between -> this series of colored lines is called a line or atomic spectra. Each element produces a unique set of spectral lines. no two elements emit the same spectral lines, elements can be identified by their line spectrum.
21 ATOMIC SPECTRA - examples The visible light spectrum is displayed at the top and line spectra for three elements - hydrogen, neon, and iron - are below.
22 Ionizing radiation is emitted when radioactive substances decay. Radioactive decay occurs when the nucleus of an atom spontaneously decays by emitting a particle. The four forms of ionizing radiation are: alpha particles beta particles gamma rays and indirectly, neutrons. All have enough energy to ionize atoms, in other words, remove one or more of the atom s electrons.
23 A nuclei which emits energy in the form of radiation is known parent radionuclide, which further transform to an atom with a nucleus in a different nucleus containing different numbers of nucleons. These new elements formed during the radioactive decay are known as daughter nuclei.
24 alpha particle 2 protons and 2 neutrons the equivalent of the nucleus of a helium atom. α particles readily ionize material they contact and transfer energy to that material s electrons. An α particle can travel several millimeters in air, but in general its range decreases with increasing density of the medium. α particles do not penetrate the outer layer of human skin, but if inhaled, alpha particles can damage lung tissue.
25 95 Am241 Np He U238 Th He Th Ra He Pu U He U Th He 4 88 Ra He 4
26 beta particle an electron -> effect of Negative beta decay an positron -> effect of Positive beta decay much lighter than an alpha particle. Thus, it takes beta particles a longer distance than alpha particles to lose energy. A medium-energy beta particle travels about one meter in air and one millimeter in body tissue.
27 beta minus decay beta decay does not change the mass number of the nucleus -> result in an increase of +1 in the atomic number because of the addition of a proton in the daughter nucleus beta decay decreases the neutron-to-proton ratio, moving the nucleus toward the band of stable nuclei.
28 beta plus decay beta decay does not change the mass number of the nucleus positron has the same mass as an electron but opposite charge, positron emission is the opposite of beta minus decay. Thus positron emission is characteristic of neutron-poor nuclei, which decay by transforming a proton to a neutron and emitting a high-energy positron
29 in positron decay a proton decays into a neutron, a positron with a neutrino particle.
30
31 Gamma rays electromagnetic radiation A radioactive element may emit gamma rays (quanta, called photons) if the nucleus remaining after alpha or beta decay is in an excited state undergoes a transition to a lower-energy state by emitting a γ ray Gamma rays can penetrate much more deeply than alpha or beta particles; a high-energy gamma ray photon may pass through a person without interacting with tissue at all. When gamma rays interact with tissue, they ionize atoms.
32 X-Ray Emission Part of the electromagnetic spectrum with the wavelength range 10-8 m to m In electron capture (EC), an electron in an inner shell reacts with a proton to produce a neutron, with emission of an x-ray. The mass number does not change, but the atomic number of the daughter is lower by 1 than the parent W.C Roentgen, a German physicist discovered X-Rays in the year A photographic film wrapped in black color paper was found to be exposed when placed near a cathode-ray tube. Roentgen concluded that some invisible rays must have been emitted by the cathode ray tube and that it must have penetrated the black paper and hence could expose the photographic film.
33 Neutrons Unlike alpha and beta particles, they do not interact with electrons or cause ionization directly. however can ionize indirectly in a variety of ways: elastic collisions, inelastic scattering, nonelastic scattering, capture reactions, or spallation processes. These processes variously result in the emission of gamma rays, beta radiation, and, in the case of spallation, more neutrons.
34
35 Ionizing radiation can be measured using units of electron volts, ergs, and joules The electron-volt (ev) - unit of energy associated with moving electrons around. An electron is tightly bound in a hydrogen atom (1 proton & 1 electron). It takes 13.6 electron-volts of energy to move this electron completely away from the proton. The atom is ionized The ionization energy of the tightly bound electron in hydrogen is 13.6 electron volts.
36 Mesuring Radioactivity The radioactivity of a substance is measured in the number of nuclei that decay per unit time. The standard international unit or radioactivity is called a becquerel (abbreviated Bq), which is equal to one disintegration per second (dps). Radioactivity is also measured in curies, a historical unit based on the number of disintegration per second in one gram of radium-226 (37 billion). 1 curie = 37 billion Bq. One picocurie (a trillionth of a curie) = Bq, and 1 Bq = 27 picocuries. Radioactivity is also measured in disintegration per minute (dpm). One dpm = 1/60 Bq.
37 Specific activity measures the radioactivity of a unit weight of substance. The units are curies per gram or becquerels per gram. This allows us to compare whether a substance is more or less radioactive than another. The specific activity of a radionuclide is inversely proportional to its atomic weight and its half-life.
38 Environmental and biological measurements of radioactivity are generally expressed as concentrations of radioactivity in soil, water, air, or tissue. Examples of units: picocuries per liter, becquerels per cubic meter picocuries per gram disintegrations per minute per 100 square centimeters. One picocurie (abbreviated pci) is (or ) curie.
39 The Becquerel (Bq) measures the activity of a radioactive source, giving the number of atoms which, within a particular time frame, transform and emit radiation. 1 Bq = 1 emission of radiation per second. 1 MBq = 1 mega Becquerel = 1,000,000 Bq 1 GBq = 1 giga Becquerel = 1,000,000,000 Bq 1 TBq = 1 tera Becquerel = 1,000,000,000,000 Bq
40 ABSORBING the exposure Placing your body near a radioactive source results in exposure. To evaluate the hazard from this exposure one must compute the absorbed dose. This is defined as the energy imparted to a defined mass of tissue. Dose is generally not uniform over the body. A radioactive substance can be selectively taken up by different organs or tissue.
41 Measuring the absorbed dose: GRAY & RAD The Gray (Gy) measures the absorbed dose, giving the energy transferred by ionizing radiations to the material upon encountering it. 1 Gy = 1 joule per kilogram = 100 rads 1 mgy = 1 milligray = Gy 1 μgy = 1 microgray = Gy 1 ngy = 1 nanogray = Gy Radiation doses are often calculated in the units of rad (radiation absorbeddose). One rad is 100 ergs/gram, 100 ergs of energy absorbed by one gram of a given body tissue.
42 MEASURING THE BIOLOGICAL EFFECT: THE SIEVERT The Sievert (Sv) evaluates the effects of ionizing radiation on living material. At equal doses, the effects of radioactivity on living tissue depends on the type of radiation (alpha, beta, gamma, etc.), on the organ concerned and also on the length of exposure. 1 msv = 1 millisievert = Sv 1 µsv = 1 microsievert = Sv
43
44
45
46 Some units used in measuring ionizing radiation and radiation dose Unit Description Equivalent Rem (roentgen equivalent man) A unit of equivalent absorbed dose of radiation which takes into account the relative biological effectiveness of different forms of ionizing radiation, or the varying ways in which they transfer their energy to human tissue. The dose in rem equals the dose in rad multiplied by the quality factor (Q). Sievert (Sv) A unit of equivalent absorbed dose equal to 100 rem. Rad (radiation absorbed dose) Gray (Gy) Curie (Ci) Becquerel s (Bq) Disintegration s per second (dps) A unit of absorbed dose of radiation. Rad is a measure of the amount of energy deposited in tissue. A unit of absorbed radiation dose equal to 100 rad. Gray is a measure of deposition of energy in tissue. The traditional unit of radioactivity, equal to the radioactivity of one gram of pure radium-226. The standard international unit of radioactivity equal to one disintegration per second. The number of subatomic particles (e.g. alpha particles) or photons (gamma rays) released from the nucleus of a given atom over one second. One dps = 60 dpm (disintegrations per minute). rem = rad x Q Q=20 for beta and gamma radiation Q= 10 for neutrons 1 Sv = 100 rem Sv = Gy x Q 1 rad = 100 erg/gram 1 Gy = 100 rad 1 Ci = 37 billion dps = 37 billion Bq 1 Bq = 27 pci 1 dps = 1 Bq
47 Links to additional pages Animation of Bohr's Model c-theory-ii/51 Nuclear Reactions
48 Questions What is an alfa and beta decay? What is isotope? What are the units to mesure radioactivity? What are the units to mesure dose of absorption? What is a nuclide / Stable / unstable nuclide What is nuclear force? Absorption Spectrum and Emission Spectrum of an atom Rutheford / Bohr and Schrodinger models of atom structure What are neutrons for? Write a balanced nuclear equation to describe each reaction. the beta decay of S1635 the decay of P1530 by positron emission
49 More questions What makes something radioactive? an unstable nucleus YES/NO elements with an atomic number higher than 83 YES/NO More protons than neutrons YES/NO
50 1.A 1 g sample of 207 Po is allowed to decay. It has a half life of 6 hours. How much 207 Po will remain after 12 hours? 125 mg 250 mg 333 mg 500 mg 667 mg 2.What nucleus is formed as a result of the α-decay of Po? At Po Rn Pb Hg 3.What nucleus is formed as a result of the β-minus decay of 55 24Cr? Mn Mn Cr V V
51 More questions The true test of whether an element is radioactive is whether any of its isotopes -- or configurations -- are stable. If not, the substance is radioactive. It's true that all elements with an atomic number higher than 83 are radioactive, but there are also several radioactive elements with lower atomic numbers. What makes something radioactive? an unstable nucleus YES/NO elements with an atomic number higher than 83 YES/NO More protons than neutrons YES/NO
U (superscript is mass number, subscript atomic number) - radionuclides nuclei that are radioactive - radioisotopes atoms containing radionuclides
Chapter : Nuclear Chemistry. Radioactivity nucleons neutron and proton all atoms of a given element have the same number of protons, atomic number isotopes atoms with the same atomic number but different
More informationRadioactivity. General Physics II PHYS 111. King Saud University College of Applied Studies and Community Service Department of Natural Sciences
King Saud University College of Applied Studies and Community Service Department of Natural Sciences Radioactivity General Physics II PHYS 111 Nouf Alkathran nalkathran@ksu.edu.sa Outline Radioactive Decay
More informationAlpha decay usually occurs in heavy nuclei such as uranium or plutonium, and therefore is a major part of the radioactive fallout from a nuclear
Radioactive Decay Radioactivity is the spontaneous disintegration of atomic nuclei. This phenomenon was first reported in 1896 by the French physicist Henri Becquerel. Marie Curie and her husband Pierre
More informationAbsorber Alpha emission Alpha particle Atom. Atomic line spectra Atomic mass unit Atomic number Atomic structure. Background radiation
Material that prevent radioactive emission from passing through it Release of alpha particle from unstable nucleus(a 2+ helium ion or a helium nucleus) The nucleus of a helium atom (two protons and two
More informationNuclear forces and Radioactivity. Two forces are at work inside the nucleus of an atom
Nuclear forces and Radioactivity Two forces are at work inside the nucleus of an atom Forces act in opposing directions Electrostatic repulsion: pushes protons apart Strong nuclear force: pulls protons
More informationWHAT IS IONIZING RADIATION
WHAT IS IONIZING RADIATION Margarita Saraví National Atomic Energy Commission - Argentina Workshop on Ionizing Radiation SIM Buenos Aires 10 November 2011 What is ionizing radiation? What is ionizing radiation?
More informationChapter 22 - Nuclear Chemistry
Chapter - Nuclear Chemistry - The Nucleus I. Introduction A. Nucleons. Neutrons and protons B. Nuclides. Atoms identified by the number of protons and neutrons in the nucleus 8 a. radium-8 or 88 Ra II.
More informationUnit 1 Atomic Structure
Unit 1 Atomic Structure 3-1 The Atom: From Philosophical Idea to Scientific Theory I. Atomic Theory A. Modern Atomic Theory 1. All matter is made up of very tiny particles called atoms 2. Atoms of the
More informationUnit 1 Atomic Structure
Unit 1 Atomic Structure Defining the Atom I. Atomic Theory A. Modern Atomic Theory 1. All matter is made up of very tiny particles called atoms 2. Atoms of the same element are chemically alike 3. Individual
More informationChapter 18 Nuclear Chemistry
Chapter 8 Nuclear Chemistry 8. Discovery of radioactivity 895 Roentgen discovery of radioactivity X-ray X-ray could penetrate other bodies and affect photographic plates led to the development of X-ray
More informationPS-21 First Spring Institute say : Teaching Physical Science. Radioactivity
PS-21 First Spring Institute say 2012-2013: Teaching Physical Science Radioactivity What Is Radioactivity? Radioactivity is the release of tiny, highenergy particles or gamma rays from the nucleus of an
More informationChapter 21. Preview. Lesson Starter Objectives Mass Defect and Nuclear Stability Nucleons and Nuclear Stability Nuclear Reactions
Preview Lesson Starter Objectives Mass Defect and Nuclear Stability Nucleons and Nuclear Stability Nuclear Reactions Section 1 The Nucleus Lesson Starter Nuclear reactions result in much larger energy
More informationRadioactivity. General Physics II PHYS 111. King Saud University College of Applied Studies and Community Service Department of Natural Sciences
King Saud University College of Applied Studies and Community Service Department of Natural Sciences Radioactivity General Physics II PHYS 111 Nouf Alkathran nalkathran@ksu.edu.sa Outline Radioactive Decay
More informationRadiation Terminology
Radiation Terminology This section discusses the terms and concepts which are necessary for a meaningful discussion of radiation, its sources, and its risks. USNRC Technical Training Center 5-1 0703 Energy
More informationNuclear Spectroscopy: Radioactivity and Half Life
Particle and Spectroscopy: and Half Life 02/08/2018 My Office Hours: Thursday 1:00-3:00 PM 212 Keen Building Outline 1 2 3 4 5 Some nuclei are unstable and decay spontaneously into two or more particles.
More informationThe basic structure of an atom is a positively charged nucleus composed of both protons and neutrons surrounded by negatively charged electrons.
4.4 Atomic structure Ionising radiation is hazardous but can be very useful. Although radioactivity was discovered over a century ago, it took many nuclear physicists several decades to understand the
More informationChapter 18: Radioactivity And Nuclear Transformation. Presented by Mingxiong Huang, Ph.D.,
Chapter 18: Radioactivity And Nuclear Transformation Presented by Mingxiong Huang, Ph.D., mxhuang@ucsd.edu 18.1 Radionuclide Decay Terms and Relationships Activity Decay Constant Physical Half-Life Fundamental
More information4.4.1 Atoms and isotopes The structure of an atom Mass number, atomic number and isotopes. Content
4.4 Atomic structure Ionising radiation is hazardous but can be very useful. Although radioactivity was discovered over a century ago, it took many nuclear physicists several decades to understand the
More informationNuclear Chemistry. Nuclear Terminology
Nuclear Chemistry Up to now, we have been concerned mainly with the electrons in the elements the nucleus has just been a positively charged things that attracts electrons The nucleus may also undergo
More informationInteraction of the radiation with a molecule knocks an electron from the molecule. a. Molecule ¾ ¾ ¾ ion + e -
Interaction of the radiation with a molecule knocks an electron from the molecule. radiation a. Molecule ¾ ¾ ¾ ion + e - This can destroy the delicate balance of chemical reactions in living cells. The
More informationZX or X-A where X is chemical symbol of element. common unit: [unified mass unit = u] also known as [atomic mass unit = amu] or [Dalton = Da]
1 Part 5: Nuclear Physics 5.1. The Nucleus = atomic number = number of protons N = neutron number = number of neutrons = mass number = + N Representations: X or X- where X is chemical symbol of element
More informationChapter 3. Radioactivity. Table of Contents
Radioactivity Table of Contents Introduction 1. Radioactivity 2. Types of Radioactive Decays 3. Natural Radioactivity 4. Artificial Radioactivity 5. The Rate of Radioactive Decay 6. The Effects of Radiation
More informationAtomic Structure Summary
Atomic Structure Summary All atoms have: a positively charged nucleus and negatively charged electrons around it Atomic nucleus consists of: positively charged protons and neutrons that have no electric
More informationChapter 20 Nuclear Chemistry. 1. Nuclear Reactions and Their Characteristics
Chapter 2 Nuclear Chemistry 1. Nuclear Reactions and Their Characteristics Nuclear reactions involve the particles located in the nucleus of the atom: nucleons:. An atom is characterized by its atomic
More informationSources of Radiation
Radioactivity Sources of Radiation Natural Sources Cosmic Radiation The Earth is constantly bombarded by radiation from outside our solar system. interacts in the atmosphere to create secondary radiation
More informationNOTES: 25.2 Nuclear Stability and Radioactive Decay
NOTES: 25.2 Nuclear Stability and Radioactive Decay Why does the nucleus stay together? STRONG NUCLEAR FORCE Short range, attractive force that acts among nuclear particles Nuclear particles attract one
More informationThe Nature of Radioactivity. Chapter 19 Nuclear Chemistry. The Nature of Radioactivity. Nuclear Reactions. Radioactive Series
John W. Moore Conrad L. Stanitsi Peter C. Jurs http://academic.cengage.com/chemistry/moore Chapter 9 Nuclear Chemistry Stephen C. Foster Mississippi State University The Nature of Radioactivity Henri Becquerel
More informationCh05. Radiation. Energy and matter that comes from the nucleus of an atom. version 1.6
Ch05 Radiation Energy and matter that comes from the nucleus of an atom. version 1.6 Nick DeMello, PhD. 2007-2016 Ch05 Radiation The Discovery of Radioactivity Phosphorescence Radioactive history Antoine
More informationChapter 20: Phenomena. Chapter 20: The Nucleus: A Chemist s View. Nuclear Decay. Nuclear Decay. Nuclear Decay. Nuclear Decay
Chapter 20: Phenomena Phenomena: Below is a list of stable isotopes of different elements. Examine the data and see what patterns you can identify. The mass of a electron is 0.00055 u, the mass of a proton
More informationNuclear Chemistry. In this chapter we will look at two types of nuclear reactions.
1 1 Nuclear Chemistry In this chapter we will look at two types of nuclear reactions. Radioactive decay is the process in which a nucleus spontaneously disintegrates, giving off radiation. Nuclear bombardment
More informationGLOSSARY OF BASIC RADIATION PROTECTION TERMINOLOGY
GLOSSARY OF BASIC RADIATION PROTECTION TERMINOLOGY ABSORBED DOSE: The amount of energy absorbed, as a result of radiation passing through a material, per unit mass of material. Measured in rads (1 rad
More informationNuclear Chemistry. Radioactivity. In this chapter we will look at two types of nuclear reactions.
1 Nuclear Chemistry In this chapter we will look at two types of nuclear reactions. Radioactive decay is the process in which a nucleus spontaneously disintegrates, giving off radiation. Nuclear bombardment
More informationChapter 11 Nuclear Chemistry
Chapter 11 Nuclear Chemistry 11.1 Nuclear Reactions Nuclear reactions involve the particles located in the nucleus of the atom: The nucleus contains: An atom is characterized by: X A Z - Z the gives the
More informationIntroduction to Ionizing Radiation
Introduction to Ionizing Radiation Bob Curtis OSHA Salt Lake Technical Center Supplement to Lecture Outline V. 10.02 Basic Model of a Neutral Atom Electrons(-) orbiting nucleus of protons(+) and neutrons.
More informationChapter 21 Nuclear Chemistry: the study of nuclear reactions
Chapter 2 Nuclear Chemistry: the study of nuclear reactions Learning goals and key skills: Write balanced nuclear equations Know the difference between fission and fusion Predict nuclear stability in terms
More informationCHEMISTRY Topic #1: Atomic Structure and Nuclear Chemistry Fall 2017 Dr. Susan Findlay See Exercises 2.3 to 2.6
CHEMISTRY 1000 Topic #1: Atomic Structure and Nuclear Chemistry Fall 2017 Dr. Susan Findlay See Exercises 2.3 to 2.6 Balancing Nuclear Reactions mass number (A) atomic number (Z) 12 6 C In an ordinary
More informationNumber of protons. 2. What is the nuclear symbol for a radioactive isotope of copper with a mass number of 60? A) Cu
Chapter 5 Nuclear Chemistry Practice Problems 1. Fill in the missing information in the chart: Medical Use Atomic Mass symbol number Heart imaging 201 Tl 81 Number of protons Number of neutrons Abdominal
More informationLecture Presentation. Chapter 21. Nuclear Chemistry. James F. Kirby Quinnipiac University Hamden, CT Pearson Education, Inc.
Lecture Presentation Chapter 21, Inc. James F. Kirby Quinnipiac University Hamden, CT Energy: Chemical vs. Chemical energy is associated with making and breaking chemical bonds. energy is enormous in comparison.
More information1.1 ALPHA DECAY 1.2 BETA MINUS DECAY 1.3 GAMMA EMISSION 1.4 ELECTRON CAPTURE/BETA PLUS DECAY 1.5 NEUTRON EMISSION 1.6 SPONTANEOUS FISSION
Chapter NP-3 Nuclear Physics Decay Modes and Decay Rates TABLE OF CONTENTS INTRODUCTION OBJECTIVES 1.0 RADIOACTIVE DECAY 1.1 ALPHA DECAY 1.2 BETA MINUS DECAY 1.3 GAMMA EMISSION 1.4 ELECTRON CAPTURE/BETA
More informationNuclear Chemistry AP Chemistry Lecture Outline
Nuclear Chemistry AP Chemistry Lecture Outline Name: involve changes with electrons. involve changes in atomic nuclei. Spontaneously-changing nuclei emit and are said to be. Radioactivity nucleons: mass
More informationChemistry 201: General Chemistry II - Lecture
Chemistry 201: General Chemistry II - Lecture Dr. Namphol Sinkaset Chapter 21 Study Guide Concepts 1. There are several modes of radioactive decay: (1) alpha (α) decay, (2) beta (β) decay, (3) gamma (γ)
More informationNuclear Radiation. Natural Radioactivity. A person working with radioisotopes wears protective clothing and gloves and stands behind a shield.
Nuclear Radiation Natural Radioactivity A person working with radioisotopes wears protective clothing and gloves and stands behind a shield. 1 Radioactive Isotopes A radioactive isotope has an unstable
More informationCH 222 Chapter Twenty-one Concept Guide
CH 222 Chapter Twenty-one Concept Guide 1. Terminology Alpha Radiation (α): Beta Radiation (β): Gamma Radiation (γ): Nuclear Reaction: Nucleons: Radioactive Decay Series: Positrons: Nuclear Binding Energy:
More informationAPPENDIX A RADIATION OVERVIEW
Former NAVWPNSTA Concord, Inland Area APPENDIX A RADIATION OVERVIEW Draft ECSD-3211-0005-0004 08/2009 This page intentionally left blank. Draft ECSD-3211-0005-0004 08/2009 APPENDIX A RADIATION OVERVIEW
More informationChemistry 52 Chapter 11 ATOMIC STRUCTURE. The general designation for an atom is shown below:
ATOMIC STRUCTURE An atom is composed of a positive nucleus surrounded by negatively charged electrons. The nucleus is composed of protons and neutrons. The protons and neutrons in a nucleus are referred
More informationAtoms and Nuclear Chemistry. Atoms Isotopes Calculating Average Atomic Mass Radioactivity
Atoms and Nuclear Chemistry Atoms Isotopes Calculating Average Atomic Mass Radioactivity Atoms An atom is the smallest particle of an element that has all of the properties of that element. Composition
More informationda u g ht er + radiation
RADIOACTIVITY The discovery of radioactivity can be attributed to several scientists. Wilhelm Roentgen discovered X-rays in 1895 and shortly after that Henri Becquerel observed radioactive behavior while
More informationNuclear Chemistry. Technology Strategies for Success PO Box 1485 East Northport, NY (631) NYS-PREP
Nuclear Chemistry Technology Strategies for Success PO Box 1485 East Northport, NY 11725 (631)734-0115 1-888-NYS-PREP techstrategies@gmail.com Nuclear Chemistry Table of Contents 1.0 Nuclear Chemistry...3
More informationChapter 37. Nuclear Chemistry. Copyright (c) 2011 by Michael A. Janusa, PhD. All rights reserved.
Chapter 37 Nuclear Chemistry Copyright (c) 2 by Michael A. Janusa, PhD. All rights reserved. 37. Radioactivity Radioactive decay is the process in which a nucleus spontaneously disintegrates, giving off
More informationChemistry: The Central Science. Chapter 21: Nuclear Chemistry
Chemistry: The Central Science Chapter 21: Nuclear Chemistry A nuclear reaction involves changes in the nucleus of an atom Nuclear chemistry the study of nuclear reactions, with an emphasis in their uses
More information6. Atomic and Nuclear Physics
6. Atomic and Nuclear Physics Chapter 6.2 Radioactivity From IB OCC, prepared by J. Domingues based on Tsokos Physics book Warm Up Define: nucleon atomic number mass number isotope. Radioactivity In 1896,
More informationChapter 10. Section 10.1 What is Radioactivity?
Chapter 10 Section 10.1 What is Radioactivity? What happens when an element undergoes radioactive decay? How does radiation affect the nucleus of an unstable isotope? How do scientists predict when an
More informationChapter Four (Interaction of Radiation with Matter)
Al-Mustansiriyah University College of Science Physics Department Fourth Grade Nuclear Physics Dr. Ali A. Ridha Chapter Four (Interaction of Radiation with Matter) Different types of radiation interact
More informationChapter. Nuclear Chemistry
Chapter Nuclear Chemistry Nuclear Reactions 01 Chapter 22 Slide 2 Chapter 22 Slide 3 Alpha Decay: Loss of an α-particle (a helium nucleus) 4 2 He 238 92 U 234 4 U He 90 + 2 Chapter 22 Slide 4 Beta Decay:
More informationRadiation Safety Basic Terms
Radiation Safety Basic Terms Radiation Radiation is energy in transit in the form of high speed particles and electromagnetic waves. We encounter electromagnetic waves every day. They make up our visible
More informationD) g. 2. In which pair do the particles have approximately the same mass?
1. A student constructs a model for comparing the masses of subatomic particles. The student selects a small, metal sphere with a mass of gram to represent an electron. A sphere with which mass would be
More informationLecture PowerPoints. Chapter 31 Physics: Principles with Applications, 7th edition Giancoli
Lecture PowerPoints Chapter 31 Physics: Principles with Applications, 7th edition Giancoli This work is protected by United States copyright laws and is provided solely for the use of instructors in teaching
More informationNuclear Decays. Alpha Decay
Nuclear Decays The first evidence of radioactivity was a photographic plate, wrapped in black paper and placed under a piece of uranium salt by Henri Becquerel on February 26, 1896. Like many events in
More informationIntroduction to Nuclear Engineering. Ahmad Al Khatibeh
Introduction to Nuclear Engineering Ahmad Al Khatibeh CONTENTS INTRODUCTION (Revision) RADIOACTIVITY Radioactive Decay Rates Units of Measurement for Radioactivity Variation of Radioactivity Over Time.
More informationUnits and Definition
RADIATION SOURCES Units and Definition Activity (Radioactivity) Definition Activity: Rate of decay (transformation or disintegration) is described by its activity Activity = number of atoms that decay
More informationRadiation Safety Training Session 1: Radiation Protection Fundamentals and Biological Effects
Radiation Safety Training Session 1: Radiation Protection Fundamentals and Biological Effects Reading Assignment: LLE Radiological Controls Manual (LLEINST 6610) Part 1 UR Radiation Safety Training Manual
More informationBasic science. Atomic structure. Electrons. The Rutherford-Bohr model of an atom. Electron shells. Types of Electrons. Describing an Atom
Basic science A knowledge of basic physics is essential to understanding how radiation originates and behaves. This chapter works through what an atom is; what keeps it stable vs. radioactive and unstable;
More informationCollege Physics B - PHY2054C
College - PHY2054C Physics - Radioactivity 11/24/2014 My Office Hours: Tuesday 10:00 AM - Noon 206 Keen Building Review Question 1 Isotopes of an element A have the same number of protons and electrons,
More informationChapter 30 Nuclear Physics and Radioactivity
Chapter 30 Nuclear Physics and Radioactivity 30.1 Structure and Properties of the Nucleus Nucleus is made of protons and neutrons Proton has positive charge: Neutron is electrically neutral: 30.1 Structure
More informationRadioactivity & Nuclear. Chemistry. Mr. Matthew Totaro Legacy High School. Chemistry
Radioactivity & Nuclear Chemistry Mr. Matthew Totaro Legacy High School Chemistry The Discovery of Radioactivity Antoine-Henri Becquerel designed an experiment to determine if phosphorescent minerals also
More information= : K A
Atoms and Nuclei. State two limitations of JJ Thomson s model of atom. 2. Write the SI unit for activity of a radioactive substance. 3. What observations led JJ Thomson to conclusion that all atoms have
More informationChapter 29. Nuclear Physics
Chapter 29 Nuclear Physics Ernest Rutherford 1871 1937 Discovery that atoms could be broken apart Studied radioactivity Nobel prize in 1908 Some Properties of Nuclei All nuclei are composed of protons
More informationLecture PowerPoint. Chapter 31 Physics: Principles with Applications, 6 th edition Giancoli
Lecture PowerPoint Chapter 31 Physics: Principles with Applications, 6 th edition Giancoli 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the
More informationRadiation Protection Fundamentals and Biological Effects: Session 1
Radiation Protection Fundamentals and Biological Effects: Session 1 Reading assignment: LLE Radiological Controls Manual (LLEINST 6610): Part 1 UR Radiation Safety Training Manual and Resource Book: Parts
More informationName Date Class NUCLEAR RADIATION. alpha particle beta particle gamma ray
25.1 NUCLEAR RADIATION Section Review Objectives Explain how an unstable nucleus releases energy Describe the three main types of nuclear radiation Vocabulary radioisotopes radioactivity radiation alpha
More informationRevision Guide for Chapter 18
Revision Guide for Chapter 18 Contents Student s Checklist Revision Notes Ionising radiation... 4 Biological effects of ionising radiation... 5 Risk... 5 Nucleus... 6 Nuclear stability... 6 Binding energy...
More information3 Radioactivity - Spontaneous Nuclear Processes
3 Radioactivity - Spontaneous Nuclear Processes Becquerel was the first to detect radioactivity. In 1896 he was carrying out experiments with fluorescent salts (which contained uranium) and found that
More informationBASIC OF RADIATION; ORIGIN AND UNITS
INAYA MEDICAL COLLEGE (IMC) RAD 243 - LECTURE 2 BASIC OF RADIATION; ORIGIN AND UNITS DR. MOHAMMED MOSTAFA EMAM LECTURES & CLASS ACTIVITIES https://inayacollegedrmohammedemam.wordpress.com/ Password: drmohammedemam
More informationChapter 21
Chapter 21 http://youtu.be/kwasz59f8ga Nuclear reactions involve the nucleus The nucleus opens, and protons and neutrons are rearranged. The opening of the nucleus releases a tremendous amount of energy
More informationBasic physics of nuclear medicine
Basic physics of nuclear medicine Nuclear structure Atomic number (Z): the number of protons in a nucleus; defines the position of an element in the periodic table. Mass number (A) is the number of nucleons
More information1. This question is about the Rutherford model of the atom.
1. This question is about the Rutherford model of the atom. (a) Most alpha particles used to bombard a thin gold foil pass through the foil without a significant change in direction. A few alpha particles
More information21/11/ /11/2017 Atomic Structure AQA Physics topic 4
Atomic Structure AQA Physics topic 4 4.1 Atoms and Isotopes The structure of the atom ELECTRON negative, mass nearly nothing The nucleus is around 10,000 times smaller then the atom! NEUTRON neutral, same
More informationName: COMBINED SCIENCE Topics 4, 5 & 6 LEARNING OUTCOMES. Maintain a record of your progress Use the booklet to guide revision
Name: COMBINED SCIENCE Topics 4, 5 & 6 LEARNING OUTCOMES Maintain a record of your progress Use the booklet to guide revision Close the Gap Contemporary record of the Topics / Learning outcomes that I
More informationParticles involved proton neutron electron positron gamma ray 1
TOPIC : Nuclear and radiation chemistry Nuclide - an atom with a particular mass number and atomic number Isotopes - nuclides with the same atomic number (Z) but different mass numbers (A) Notation A Element
More informationTypes of radiation resulting from radioactive decay can be summarized in a simple chart. Only X-rays, Auger electrons and internal conversion
General information Nuclei are composed of combinations of nucleons (protons and neutrons); certain combinations of these nucleons (i.e., certain nuclides) possess a high degree of stability while others
More informationChapter 25. Nuclear Chemistry. Types of Radiation
Chapter 25 Nuclear Chemistry Chemical Reactions 1. Bonds are broken and formed 2. Atoms may rearrange, but remain unchanged 3. Involve only valence electrons 4. Small energy changes 5. Reaction rate is
More informationNuclear Physics Part 2A: Radioactive Decays
Nuclear Physics Part 2A: Radioactive Decays Last modified: 23/10/2018 Links What is a Decay? Alpha Decay Definition Q-value Example Not Every Alpha Decay is Possible Beta Decay β rays are electrons Anti-particles
More informationSECTION A Quantum Physics and Atom Models
AP Physics Multiple Choice Practice Modern Physics SECTION A Quantum Physics and Atom Models 1. Light of a single frequency falls on a photoelectric material but no electrons are emitted. Electrons may
More informationThe Atomic Nucleus & Radioactive Decay. Major Constituents of an Atom 4/28/2016. Student Learning Outcomes. Analyze radioactive decay and its results
The Atomic Nucleus & Radioactive Decay ( Chapter 10) Student Learning Outcomes Analyze radioactive decay and its results Differentiate between nuclear fission and fusion Major Constituents of an Atom U=unified
More informationPhysics 3204 UNIT 3 Test Matter Energy Interface
Physics 3204 UNIT 3 Test Matter Energy Interface 2005 2006 Time: 60 minutes Total Value: 33 Marks Formulae and Constants v = f λ E = hf h f = E k + W 0 E = m c 2 p = h λ 1 A= A T 0 2 t 1 2 E k = ½ mv 2
More information10.1 RADIOACTIVE DECAY
10.1 RADIOACTIVE DECAY When Henri Becquerel placed uranium salts on a photographic plate and then developed the plate, he found a foggy image. The image was caused by rays that had not been observed before.
More informationAtomic Theory. Contribution to Modern Atomic Theory
Alief High School Chemistry STAAR Review Reporting Category 2: Atomic Structure and Nuclear Chemistry C.6.A Understand the experimental design and conclusions used in the development of modern atomic theory,
More informationChapter 18. Nuclear Chemistry
Chapter 18 Nuclear Chemistry The energy of the sun comes from nuclear reactions. Solar flares are an indication of fusion reactions occurring at a temperature of millions of degrees. Introduction to General,
More informationIntroduction to Nuclear Reactor Physics
Introduction to Nuclear Reactor Physics J. Frýbort, L. Heraltová Department of Nuclear Reactors 19 th October 2017 J. Frýbort, L. Heraltová (CTU in Prague) Introduction to Nuclear Reactor Physics 19 th
More information: When electrons bombarded surface of certain materials, invisible rays were emitted
Nuclear Chemistry Nuclear Reactions 1. Occur when nuclei emit particles and/or rays. 2. Atoms are often converted into atoms of another element. 3. May involve protons, neutrons, and electrons 4. Associated
More informationChapter 10 - Nuclear Physics
The release of atomic energy has not created a new problem. It has merely made more urgent the necessity of solving an existing one. -Albert Einstein David J. Starling Penn State Hazleton PHYS 214 Ernest
More informationChemistry 19 Prep Test - Nuclear Processes
Chapter 9 Prep-Test Chemistry 9 Prep Test - Nuclear Processes Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.. Which of the illustrations above
More informationNuclear Science A Teacher s Guide to the Nuclear Science Wall Chart 1998 Contemporary Physics Education Project (CPEP)
Nuclear Science A Teacher s Guide to the Nuclear Science Wall Chart 1998 Contemporary Physics Education Project (CPEP) Chapter 3 Radioactivity In radioactive processes, particles or electromagnetic radiation
More informationRadiation and Radioactivity. PHYS 0219 Radiation and Radioactivity
Radiation and Radioactivity 1 Radiation and Radioactivity This experiment has four parts: 1. Counting Statistics 2. Gamma (g) Ray Absorption Half-length and shielding 3. 137 Ba Decay Half-life 4. Dosimetry
More informationWhat happens during nuclear decay? During nuclear decay, atoms of one element can change into atoms of a different element altogether.
When Henri Becquerel placed uranium salts on a photographic plate and then developed the plate, he found a foggy image. The image was caused by rays that had not been observed before. For his discovery
More informationRadioactivity: the process by which atoms emit energy in the form of electromagnetic waves, charged particles, or uncharged particles.
Radioactivity: the process by which atoms emit energy in the form of electromagnetic waves, charged particles, or uncharged particles. In 1896, Henri Bequerel discovered that uranium and other elements
More informationNuclear Physics and Nuclear Reactions
Slide 1 / 33 Nuclear Physics and Nuclear Reactions The Nucleus Slide 2 / 33 Proton: The charge on a proton is +1.6x10-19 C. The mass of a proton is 1.6726x10-27 kg. Neutron: The neutron is neutral. The
More informationModule 1. An Introduction to Radiation
Module 1 An Introduction to Radiation General Definition of Radiation Ionizing radiation, for example, X-rays, gamma-rays, α particles Ionizing radiation is capable of removing an electron from the atom
More informationPhys102 Lecture 29, 30, 31 Nuclear Physics and Radioactivity
Phys10 Lecture 9, 30, 31 Nuclear Physics and Radioactivity Key Points Structure and Properties of the Nucleus Alpha, Beta and Gamma Decays References 30-1,,3,4,5,6,7. Atomic Structure Nitrogen (N) Atom
More informationNuclear Physics and Radioactivity
Nuclear Physics and Radioactivity Structure and Properties of the Nucleus Nucleus is made of protons and neutrons Proton has positive charge: Neutron is electrically neutral: Neutrons and protons are collectively
More information