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College Physics

A | Atomic Masses

College PhysicsA | Atomic Masses

Table of contents
  1. Preface
  2. 1 Introduction: The Nature of Science and Physics
    1. Introduction to Science and the Realm of Physics, Physical Quantities, and Units
    2. 1.1 Physics: An Introduction
    3. 1.2 Physical Quantities and Units
    4. 1.3 Accuracy, Precision, and Significant Figures
    5. 1.4 Approximation
    6. Glossary
    7. Section Summary
    8. Conceptual Questions
    9. Problems & Exercises
  3. 2 Kinematics
    1. Introduction to One-Dimensional Kinematics
    2. 2.1 Displacement
    3. 2.2 Vectors, Scalars, and Coordinate Systems
    4. 2.3 Time, Velocity, and Speed
    5. 2.4 Acceleration
    6. 2.5 Motion Equations for Constant Acceleration in One Dimension
    7. 2.6 Problem-Solving Basics for One-Dimensional Kinematics
    8. 2.7 Falling Objects
    9. 2.8 Graphical Analysis of One-Dimensional Motion
    10. Glossary
    11. Section Summary
    12. Conceptual Questions
    13. Problems & Exercises
  4. 3 Two-Dimensional Kinematics
    1. Introduction to Two-Dimensional Kinematics
    2. 3.1 Kinematics in Two Dimensions: An Introduction
    3. 3.2 Vector Addition and Subtraction: Graphical Methods
    4. 3.3 Vector Addition and Subtraction: Analytical Methods
    5. 3.4 Projectile Motion
    6. 3.5 Addition of Velocities
    7. Glossary
    8. Section Summary
    9. Conceptual Questions
    10. Problems & Exercises
  5. 4 Dynamics: Force and Newton's Laws of Motion
    1. Introduction to Dynamics: Newton’s Laws of Motion
    2. 4.1 Development of Force Concept
    3. 4.2 Newton’s First Law of Motion: Inertia
    4. 4.3 Newton’s Second Law of Motion: Concept of a System
    5. 4.4 Newton’s Third Law of Motion: Symmetry in Forces
    6. 4.5 Normal, Tension, and Other Examples of Forces
    7. 4.6 Problem-Solving Strategies
    8. 4.7 Further Applications of Newton’s Laws of Motion
    9. 4.8 Extended Topic: The Four Basic Forces—An Introduction
    10. Glossary
    11. Section Summary
    12. Conceptual Questions
    13. Problems & Exercises
  6. 5 Further Applications of Newton's Laws: Friction, Drag, and Elasticity
    1. Introduction: Further Applications of Newton’s Laws
    2. 5.1 Friction
    3. 5.2 Drag Forces
    4. 5.3 Elasticity: Stress and Strain
    5. Glossary
    6. Section Summary
    7. Conceptual Questions
    8. Problems & Exercises
  7. 6 Uniform Circular Motion and Gravitation
    1. Introduction to Uniform Circular Motion and Gravitation
    2. 6.1 Rotation Angle and Angular Velocity
    3. 6.2 Centripetal Acceleration
    4. 6.3 Centripetal Force
    5. 6.4 Fictitious Forces and Non-inertial Frames: The Coriolis Force
    6. 6.5 Newton’s Universal Law of Gravitation
    7. 6.6 Satellites and Kepler’s Laws: An Argument for Simplicity
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  8. 7 Work, Energy, and Energy Resources
    1. Introduction to Work, Energy, and Energy Resources
    2. 7.1 Work: The Scientific Definition
    3. 7.2 Kinetic Energy and the Work-Energy Theorem
    4. 7.3 Gravitational Potential Energy
    5. 7.4 Conservative Forces and Potential Energy
    6. 7.5 Nonconservative Forces
    7. 7.6 Conservation of Energy
    8. 7.7 Power
    9. 7.8 Work, Energy, and Power in Humans
    10. 7.9 World Energy Use
    11. Glossary
    12. Section Summary
    13. Conceptual Questions
    14. Problems & Exercises
  9. 8 Linear Momentum and Collisions
    1. Introduction to Linear Momentum and Collisions
    2. 8.1 Linear Momentum and Force
    3. 8.2 Impulse
    4. 8.3 Conservation of Momentum
    5. 8.4 Elastic Collisions in One Dimension
    6. 8.5 Inelastic Collisions in One Dimension
    7. 8.6 Collisions of Point Masses in Two Dimensions
    8. 8.7 Introduction to Rocket Propulsion
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  10. 9 Statics and Torque
    1. Introduction to Statics and Torque
    2. 9.1 The First Condition for Equilibrium
    3. 9.2 The Second Condition for Equilibrium
    4. 9.3 Stability
    5. 9.4 Applications of Statics, Including Problem-Solving Strategies
    6. 9.5 Simple Machines
    7. 9.6 Forces and Torques in Muscles and Joints
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  11. 10 Rotational Motion and Angular Momentum
    1. Introduction to Rotational Motion and Angular Momentum
    2. 10.1 Angular Acceleration
    3. 10.2 Kinematics of Rotational Motion
    4. 10.3 Dynamics of Rotational Motion: Rotational Inertia
    5. 10.4 Rotational Kinetic Energy: Work and Energy Revisited
    6. 10.5 Angular Momentum and Its Conservation
    7. 10.6 Collisions of Extended Bodies in Two Dimensions
    8. 10.7 Gyroscopic Effects: Vector Aspects of Angular Momentum
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  12. 11 Fluid Statics
    1. Introduction to Fluid Statics
    2. 11.1 What Is a Fluid?
    3. 11.2 Density
    4. 11.3 Pressure
    5. 11.4 Variation of Pressure with Depth in a Fluid
    6. 11.5 Pascal’s Principle
    7. 11.6 Gauge Pressure, Absolute Pressure, and Pressure Measurement
    8. 11.7 Archimedes’ Principle
    9. 11.8 Cohesion and Adhesion in Liquids: Surface Tension and Capillary Action
    10. 11.9 Pressures in the Body
    11. Glossary
    12. Section Summary
    13. Conceptual Questions
    14. Problems & Exercises
  13. 12 Fluid Dynamics and Its Biological and Medical Applications
    1. Introduction to Fluid Dynamics and Its Biological and Medical Applications
    2. 12.1 Flow Rate and Its Relation to Velocity
    3. 12.2 Bernoulli’s Equation
    4. 12.3 The Most General Applications of Bernoulli’s Equation
    5. 12.4 Viscosity and Laminar Flow; Poiseuille’s Law
    6. 12.5 The Onset of Turbulence
    7. 12.6 Motion of an Object in a Viscous Fluid
    8. 12.7 Molecular Transport Phenomena: Diffusion, Osmosis, and Related Processes
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  14. 13 Temperature, Kinetic Theory, and the Gas Laws
    1. Introduction to Temperature, Kinetic Theory, and the Gas Laws
    2. 13.1 Temperature
    3. 13.2 Thermal Expansion of Solids and Liquids
    4. 13.3 The Ideal Gas Law
    5. 13.4 Kinetic Theory: Atomic and Molecular Explanation of Pressure and Temperature
    6. 13.5 Phase Changes
    7. 13.6 Humidity, Evaporation, and Boiling
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  15. 14 Heat and Heat Transfer Methods
    1. Introduction to Heat and Heat Transfer Methods
    2. 14.1 Heat
    3. 14.2 Temperature Change and Heat Capacity
    4. 14.3 Phase Change and Latent Heat
    5. 14.4 Heat Transfer Methods
    6. 14.5 Conduction
    7. 14.6 Convection
    8. 14.7 Radiation
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  16. 15 Thermodynamics
    1. Introduction to Thermodynamics
    2. 15.1 The First Law of Thermodynamics
    3. 15.2 The First Law of Thermodynamics and Some Simple Processes
    4. 15.3 Introduction to the Second Law of Thermodynamics: Heat Engines and Their Efficiency
    5. 15.4 Carnot’s Perfect Heat Engine: The Second Law of Thermodynamics Restated
    6. 15.5 Applications of Thermodynamics: Heat Pumps and Refrigerators
    7. 15.6 Entropy and the Second Law of Thermodynamics: Disorder and the Unavailability of Energy
    8. 15.7 Statistical Interpretation of Entropy and the Second Law of Thermodynamics: The Underlying Explanation
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  17. 16 Oscillatory Motion and Waves
    1. Introduction to Oscillatory Motion and Waves
    2. 16.1 Hooke’s Law: Stress and Strain Revisited
    3. 16.2 Period and Frequency in Oscillations
    4. 16.3 Simple Harmonic Motion: A Special Periodic Motion
    5. 16.4 The Simple Pendulum
    6. 16.5 Energy and the Simple Harmonic Oscillator
    7. 16.6 Uniform Circular Motion and Simple Harmonic Motion
    8. 16.7 Damped Harmonic Motion
    9. 16.8 Forced Oscillations and Resonance
    10. 16.9 Waves
    11. 16.10 Superposition and Interference
    12. 16.11 Energy in Waves: Intensity
    13. Glossary
    14. Section Summary
    15. Conceptual Questions
    16. Problems & Exercises
  18. 17 Physics of Hearing
    1. Introduction to the Physics of Hearing
    2. 17.1 Sound
    3. 17.2 Speed of Sound, Frequency, and Wavelength
    4. 17.3 Sound Intensity and Sound Level
    5. 17.4 Doppler Effect and Sonic Booms
    6. 17.5 Sound Interference and Resonance: Standing Waves in Air Columns
    7. 17.6 Hearing
    8. 17.7 Ultrasound
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  19. 18 Electric Charge and Electric Field
    1. Introduction to Electric Charge and Electric Field
    2. 18.1 Static Electricity and Charge: Conservation of Charge
    3. 18.2 Conductors and Insulators
    4. 18.3 Coulomb’s Law
    5. 18.4 Electric Field: Concept of a Field Revisited
    6. 18.5 Electric Field Lines: Multiple Charges
    7. 18.6 Electric Forces in Biology
    8. 18.7 Conductors and Electric Fields in Static Equilibrium
    9. 18.8 Applications of Electrostatics
    10. Glossary
    11. Section Summary
    12. Conceptual Questions
    13. Problems & Exercises
  20. 19 Electric Potential and Electric Field
    1. Introduction to Electric Potential and Electric Energy
    2. 19.1 Electric Potential Energy: Potential Difference
    3. 19.2 Electric Potential in a Uniform Electric Field
    4. 19.3 Electrical Potential Due to a Point Charge
    5. 19.4 Equipotential Lines
    6. 19.5 Capacitors and Dielectrics
    7. 19.6 Capacitors in Series and Parallel
    8. 19.7 Energy Stored in Capacitors
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  21. 20 Electric Current, Resistance, and Ohm's Law
    1. Introduction to Electric Current, Resistance, and Ohm's Law
    2. 20.1 Current
    3. 20.2 Ohm’s Law: Resistance and Simple Circuits
    4. 20.3 Resistance and Resistivity
    5. 20.4 Electric Power and Energy
    6. 20.5 Alternating Current versus Direct Current
    7. 20.6 Electric Hazards and the Human Body
    8. 20.7 Nerve Conduction–Electrocardiograms
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  22. 21 Circuits and DC Instruments
    1. Introduction to Circuits and DC Instruments
    2. 21.1 Resistors in Series and Parallel
    3. 21.2 Electromotive Force: Terminal Voltage
    4. 21.3 Kirchhoff’s Rules
    5. 21.4 DC Voltmeters and Ammeters
    6. 21.5 Null Measurements
    7. 21.6 DC Circuits Containing Resistors and Capacitors
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  23. 22 Magnetism
    1. Introduction to Magnetism
    2. 22.1 Magnets
    3. 22.2 Ferromagnets and Electromagnets
    4. 22.3 Magnetic Fields and Magnetic Field Lines
    5. 22.4 Magnetic Field Strength: Force on a Moving Charge in a Magnetic Field
    6. 22.5 Force on a Moving Charge in a Magnetic Field: Examples and Applications
    7. 22.6 The Hall Effect
    8. 22.7 Magnetic Force on a Current-Carrying Conductor
    9. 22.8 Torque on a Current Loop: Motors and Meters
    10. 22.9 Magnetic Fields Produced by Currents: Ampere’s Law
    11. 22.10 Magnetic Force between Two Parallel Conductors
    12. 22.11 More Applications of Magnetism
    13. Glossary
    14. Section Summary
    15. Conceptual Questions
    16. Problems & Exercises
  24. 23 Electromagnetic Induction, AC Circuits, and Electrical Technologies
    1. Introduction to Electromagnetic Induction, AC Circuits and Electrical Technologies
    2. 23.1 Induced Emf and Magnetic Flux
    3. 23.2 Faraday’s Law of Induction: Lenz’s Law
    4. 23.3 Motional Emf
    5. 23.4 Eddy Currents and Magnetic Damping
    6. 23.5 Electric Generators
    7. 23.6 Back Emf
    8. 23.7 Transformers
    9. 23.8 Electrical Safety: Systems and Devices
    10. 23.9 Inductance
    11. 23.10 RL Circuits
    12. 23.11 Reactance, Inductive and Capacitive
    13. 23.12 RLC Series AC Circuits
    14. Glossary
    15. Section Summary
    16. Conceptual Questions
    17. Problems & Exercises
  25. 24 Electromagnetic Waves
    1. Introduction to Electromagnetic Waves
    2. 24.1 Maxwell’s Equations: Electromagnetic Waves Predicted and Observed
    3. 24.2 Production of Electromagnetic Waves
    4. 24.3 The Electromagnetic Spectrum
    5. 24.4 Energy in Electromagnetic Waves
    6. Glossary
    7. Section Summary
    8. Conceptual Questions
    9. Problems & Exercises
  26. 25 Geometric Optics
    1. Introduction to Geometric Optics
    2. 25.1 The Ray Aspect of Light
    3. 25.2 The Law of Reflection
    4. 25.3 The Law of Refraction
    5. 25.4 Total Internal Reflection
    6. 25.5 Dispersion: The Rainbow and Prisms
    7. 25.6 Image Formation by Lenses
    8. 25.7 Image Formation by Mirrors
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  27. 26 Vision and Optical Instruments
    1. Introduction to Vision and Optical Instruments
    2. 26.1 Physics of the Eye
    3. 26.2 Vision Correction
    4. 26.3 Color and Color Vision
    5. 26.4 Microscopes
    6. 26.5 Telescopes
    7. 26.6 Aberrations
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  28. 27 Wave Optics
    1. Introduction to Wave Optics
    2. 27.1 The Wave Aspect of Light: Interference
    3. 27.2 Huygens's Principle: Diffraction
    4. 27.3 Young’s Double Slit Experiment
    5. 27.4 Multiple Slit Diffraction
    6. 27.5 Single Slit Diffraction
    7. 27.6 Limits of Resolution: The Rayleigh Criterion
    8. 27.7 Thin Film Interference
    9. 27.8 Polarization
    10. 27.9 *Extended Topic* Microscopy Enhanced by the Wave Characteristics of Light
    11. Glossary
    12. Section Summary
    13. Conceptual Questions
    14. Problems & Exercises
  29. 28 Special Relativity
    1. Introduction to Special Relativity
    2. 28.1 Einstein’s Postulates
    3. 28.2 Simultaneity And Time Dilation
    4. 28.3 Length Contraction
    5. 28.4 Relativistic Addition of Velocities
    6. 28.5 Relativistic Momentum
    7. 28.6 Relativistic Energy
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  30. 29 Quantum Physics
    1. Introduction to Quantum Physics
    2. 29.1 Quantization of Energy
    3. 29.2 The Photoelectric Effect
    4. 29.3 Photon Energies and the Electromagnetic Spectrum
    5. 29.4 Photon Momentum
    6. 29.5 The Particle-Wave Duality
    7. 29.6 The Wave Nature of Matter
    8. 29.7 Probability: The Heisenberg Uncertainty Principle
    9. 29.8 The Particle-Wave Duality Reviewed
    10. Glossary
    11. Section Summary
    12. Conceptual Questions
    13. Problems & Exercises
  31. 30 Atomic Physics
    1. Introduction to Atomic Physics
    2. 30.1 Discovery of the Atom
    3. 30.2 Discovery of the Parts of the Atom: Electrons and Nuclei
    4. 30.3 Bohr’s Theory of the Hydrogen Atom
    5. 30.4 X Rays: Atomic Origins and Applications
    6. 30.5 Applications of Atomic Excitations and De-Excitations
    7. 30.6 The Wave Nature of Matter Causes Quantization
    8. 30.7 Patterns in Spectra Reveal More Quantization
    9. 30.8 Quantum Numbers and Rules
    10. 30.9 The Pauli Exclusion Principle
    11. Glossary
    12. Section Summary
    13. Conceptual Questions
    14. Problems & Exercises
  32. 31 Radioactivity and Nuclear Physics
    1. Introduction to Radioactivity and Nuclear Physics
    2. 31.1 Nuclear Radioactivity
    3. 31.2 Radiation Detection and Detectors
    4. 31.3 Substructure of the Nucleus
    5. 31.4 Nuclear Decay and Conservation Laws
    6. 31.5 Half-Life and Activity
    7. 31.6 Binding Energy
    8. 31.7 Tunneling
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  33. 32 Medical Applications of Nuclear Physics
    1. Introduction to Applications of Nuclear Physics
    2. 32.1 Medical Imaging and Diagnostics
    3. 32.2 Biological Effects of Ionizing Radiation
    4. 32.3 Therapeutic Uses of Ionizing Radiation
    5. 32.4 Food Irradiation
    6. 32.5 Fusion
    7. 32.6 Fission
    8. 32.7 Nuclear Weapons
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  34. 33 Particle Physics
    1. Introduction to Particle Physics
    2. 33.1 The Yukawa Particle and the Heisenberg Uncertainty Principle Revisited
    3. 33.2 The Four Basic Forces
    4. 33.3 Accelerators Create Matter from Energy
    5. 33.4 Particles, Patterns, and Conservation Laws
    6. 33.5 Quarks: Is That All There Is?
    7. 33.6 GUTs: The Unification of Forces
    8. Glossary
    9. Section Summary
    10. Conceptual Questions
    11. Problems & Exercises
  35. 34 Frontiers of Physics
    1. Introduction to Frontiers of Physics
    2. 34.1 Cosmology and Particle Physics
    3. 34.2 General Relativity and Quantum Gravity
    4. 34.3 Superstrings
    5. 34.4 Dark Matter and Closure
    6. 34.5 Complexity and Chaos
    7. 34.6 High-temperature Superconductors
    8. 34.7 Some Questions We Know to Ask
    9. Glossary
    10. Section Summary
    11. Conceptual Questions
    12. Problems & Exercises
  36. A | Atomic Masses
  37. B | Selected Radioactive Isotopes
  38. C | Useful Information
  39. D | Glossary of Key Symbols and Notation
  40. Index
Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2
0 neutron 1 n n size 12{n} {} 1.008 665 β β size 12{β rSup { size 8{ - {}} } } {} 10.37 min
1 Hydrogen 1 1 H 1 H size 12{rSup { size 8{ 1 {}} }H} {} 1.007 825 99.985%
Deuterium 2 2 H or D 2 H or D size 12{rSup { size 8{ 2 {}} }H or D} {} 2.014 102 0.015%
Tritium 3 3 H or T 3 H or T size 12{rSup { size 8{ 3 {}} }H or T} {} 3.016 050 β β size 12{β rSup { size 8{ - {}} } } {} 12.33 y
2 Helium 3 3 He 3 He size 12{rSup { size 8{ 3 {}} }He} {} 3.016 030 1 . 38 × 10 4 % 1 . 38 × 10 4 % size 12{1 "." "38" times "10" rSup { size 8{ - 4} } %} {}
4 4 He 4 He size 12{rSup { size 8{ 4 {}} }He} {} 4.002 603 ≈100% ≈100% size 12{ approx "100"%} {}
3 Lithium 6 6 Li 6 Li size 12{rSup { size 8{ 6 {}} }Li} {} 6.015 121 7.5%
7 7 Li 7 Li size 12{rSup { size 8{ 7 {}} }Li} {} 7.016 003 92.5%
4 Beryllium 7 7 Be 7 Be size 12{rSup { size 8{ 7 {}} }Be} {} 7.016 928 EC 53.29 d
9 9 Be 9 Be size 12{rSup { size 8{ 9 {}} }Be} {} 9.012 182 100%
5 Boron 10 10 B 10 B size 12{rSup { size 8{ 10 {}} }B} {} 10.012 937 19.9%
11 11 B 11 B size 12{rSup { size 8{ 11 {}} }B} {} 11.009 305 80.1%
6 Carbon 11 11 C 11 C size 12{rSup { size 8{ 11 {}} }C} {} 11.011 432 EC, β + β + size 12{β rSup { size 8{+{}} } } {}
12 12 C 12 C size 12{rSup { size 8{ 6 {}} }Li} {} 12.000 000 98.90%
13 13 C 13 C size 12{rSup { size 8{ 13 {}} }C} {} 13.003 355 1.10%
14 14 C 14 C size 12{rSup { size 8{ 14 {}} }C} {} 14.003 241 β β size 12{β rSup { size 8{ - {}} } } {} 5730 y
7 Nitrogen 13 13 N 13 N size 12{rSup { size 8{ 13 {}} }N} {} 13.005 738 β + β + size 12{β rSup { size 8{+{}} } } {} 9.96 min
14 14 N 14 N size 12{rSup { size 8{ 14 {}} }N} {} 14.003 074 99.63%
15 15 N 15 N size 12{rSup { size 8{ 15 {}} }N} {} 15.000 108 0.37%
8 Oxygen 15 15 O 15 O size 12{rSup { size 8{ 15 {}} }O} {} 15.003 065 EC, β + β + size 12{β rSup { size 8{+{}} } } {} 122 s
16 16 O 16 O size 12{rSup { size 8{ 6 {}} }Li} {} 15.994 915 99.76%
18 18 O 18 O size 12{rSup { size 8{ 18 {}} }O} {} 17.999 160 0.200%
9 Fluorine 18 18 F 18 F size 12{rSup { size 8{ 18 {}} }F} {} 18.000 937 EC, β + β + size 12{β rSup { size 8{+{}} } } {} 1.83 h
19 19 F 19 F size 12{rSup { size 8{ 6 {}} }Li} {} 18.998 403 100%
10 Neon 20 20 Ne 20 Ne size 12{rSup { size 8{ 20 {}} }Ne} {} 19.992 435 90.51%
22 22 Ne 22 Ne size 12{rSup { size 8{ 22 {}} }Ne} {} 21.991 383 9.22%
11 Sodium 22 22 Na 22 Na size 12{rSup { size 8{ 6 {}} }Li} {} 21.994 434 β + β + size 12{β rSup { size 8{ - {}} } } {} 2.602 y
23 23 Na 23 Na size 12{rSup { size 8{ 23 {}} }Na} {} 22.989 767 100%
24 24 Na 24 Na size 12{rSup { size 8{ 24 {}} }Na} {} 23.990 961 β β size 12{β rSup { size 8{ - {}} } } {} 14.96 h
12 Magnesium 24 24 Mg 24 Mg size 12{rSup { size 8{ 24 {}} }Mg} {} 23.985 042 78.99%
13 Aluminum 27 27 Al 27 Al size 12{rSup { size 8{ 27 {}} }Al} {} 26.981 539 100%
14 Silicon 28 28 Si 28 Si size 12{rSup { size 8{ 28 {}} }Si} {} 27.976 927 92.23% 2.62h
31 31 Si 31 Si size 12{rSup { size 8{ 31 {}} }Si} {} 30.975 362 β β size 12{β rSup { size 8{ - {}} } } {}
15 Phosphorus 31 31 P 31 P size 12{rSup { size 8{ 31 {}} }P} {} 30.973 762 100%
32 32 P 32 P size 12{rSup { size 8{ 6 {}} }Li} {} 31.973 907 β β size 12{β rSup { size 8{ - {}} } } {} 14.28 d
16 Sulfur 32 32 S 32 S size 12{rSup { size 8{ 6 {}} }Li} {} 31.972 070 95.02%
35 35 S 35 S size 12{rSup { size 8{ 35 {}} }S} {} 34.969 031 β β size 12{β rSup { size 8{ - {}} } } {} 87.4 d
17 Chlorine 35 35 Cl 35 Cl size 12{rSup { size 8{ 35 {}} }Cl} {} 34.968 852 75.77%
37 37 Cl 37 Cl size 12{rSup { size 8{ 35 {}} }Cl} {} 36.965 903 24.23%
18 Argon 40 40 Ar 40 Ar size 12{rSup { size 8{ 40 {}} }Ar} {} 39.962 384 99.60%
19 Potassium 39 39 K 39 K size 12{rSup { size 8{ 39 {}} }K} {} 38.963 707 93.26%
40 40 K 40 K size 12{rSup { size 8{ 40 {}} }K} {} 39.963 999 0.0117%, EC, ββ size 12{β rSup { size 8{ - {}} } } {} 1 . 28 × 10 9 y 1 . 28 × 10 9 y size 12{1 "." "28" times "10" rSup { size 7{9} } y} {}
20 Calcium 40 40 Ca 40 Ca size 12{rSup { size 8{ 40 {}} }Ca} {} 39.962 591 96.94%
21 Scandium 45 45 Sc 45 Sc size 12{rSup { size 8{ 45 {}} }Sc} {} 44.955 910 100%
22 Titanium 48 48 Ti 48 Ti size 12{rSup { size 8{ 48 {}} }Ti} {} 47.947 947 73.8%
23 Vanadium 51 51 V 51 V size 12{rSup { size 8{ 51 {}} }V} {} 50.943 962 99.75%
24 Chromium 52 52 Cr 52 Cr size 12{rSup { size 8{ 52 {}} }Cr} {} 51.940 509 83.79%
25 Manganese 55 55 Mn 55 Mn size 12{rSup { size 8{ 55 {}} }Mn} {} 54.938 047 100%
26 Iron 56 56 Fe 56 Fe size 12{rSup { size 8{ 56 {}} }Fe} {} 55.934 939 91.72%
27 Cobalt 59 59 Co 59 Co size 12{rSup { size 8{ 59 {}} }Co} {} 58.933 198 100%
60 60 Co 60 Co size 12{rSup { size 8{ 60 {}} }Co} {} 59.933 819 β β size 12{β rSup { size 8{ - {}} } } {} 5.271 y
28 Nickel 58 58 Ni 58 Ni size 12{rSup { size 8{ 58 {}} }Ni} {} 57.935 346 68.27%
60 60 Ni 60 Ni size 12{rSup { size 8{ 60 {}} }Ni} {} 59.930 788 26.10%
29 Copper 63 63 Cu 63 Cu size 12{rSup { size 8{ 63 {}} }Cu} {} 62.939 598 69.17%
65 65 Cu 65 Cu size 12{rSup { size 8{ 65 {}} }Cu} {} 64.927 793 30.83%
30 Zinc 64 64 Zn 64 Zn size 12{rSup { size 8{ 64 {}} }Zn} {} 63.929 145 48.6%
66 66 Zn 66 Zn size 12{rSup { size 8{ 66 {}} }Zn} {} 65.926 034 27.9%
31 Gallium 69 69 Ga 69 Ga size 12{rSup { size 8{ 69 {}} }Ga} {} 68.925 580 60.1%
32 Germanium 72 72 Ge 72 Ge size 12{rSup { size 8{ 72 {}} }Ge} {} 71.922 079 27.4%
74 74 Ge 74 Ge size 12{rSup { size 8{ 74 {}} }Ge} {} 73.921 177 36.5%
33 Arsenic 75 75 As 75 As size 12{rSup { size 8{ 75 {}} }As} {} 74.921 594 100%
34 Selenium 80 80 Se 80 Se size 12{rSup { size 8{ 80 {}} }Se} {} 79.916 520 49.7%
35 Bromine 79 79 Br 79 Br size 12{rSup { size 8{ 79 {}} }Br} {} 78.918 336 50.69%
36 Krypton 84 84 Kr 84 Kr size 12{rSup { size 8{ 84 {}} }Kr} {} 83.911 507 57.0%
37 Rubidium 85 85 Rb 85 Rb size 12{rSup { size 8{ 85 {}} }Rb} {} 84.911 794 72.17%
38 Strontium 86 86 Sr 86 Sr size 12{rSup { size 8{ 86 {}} }Sr} {} 85.909 267 9.86%
88 88 Sr 88 Sr size 12{rSup { size 8{ 88 {}} }Sr} {} 87.905 619 82.58%
90 90 Sr 90 Sr size 12{rSup { size 8{ 90 {}} }Sr} {} 89.907 738 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 28.8 y
39 Yttrium 89 89 Y 89 Y size 12{rSup { size 8{ 89 {}} }Y} {} 88.905 849 100%
90 90 Y 90 Y size 12{rSup { size 8{ 90 {}} }Y} {} 89.907 152 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 64.1 h
40 Zirconium 90 90 Zr 90 Zr size 12{rSup { size 8{ 90 {}} }Zr} {} 89.904 703 51.45%
41 Niobium 93 93 Nb 93 Nb size 12{rSup { size 8{ 93 {}} }Nb} {} 92.906 377 100%
42 Molybdenum 98 98 Mo 98 Mo size 12{rSup { size 8{ 98 {}} }Mo} {} 97.905 406 24.13%
43 Technetium 98 98 Tc 98 Tc size 12{rSup { size 8{ 98 {}} }Tc} {} 97.907 215 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 4 . 2 × 10 6 y 4 . 2 × 10 6 y size 12{4 "." 2 times "10" rSup { size 8{6} } y} {}
44 Ruthenium 102 102 Ru 102 Ru size 12{rSup { size 8{ 102 {}} }Ru} {} 101.904 348 31.6%
45 Rhodium 103 103 Rh 103 Rh size 12{rSup { size 8{ 103 {}} }Rh} {} 102.905 500 100%
46 Palladium 106 106 Pd 106 Pd size 12{rSup { size 8{ 106 {}} }Pd} {} 105.903 478 27.33%
47 Silver 107 107 Ag 107 Ag size 12{rSup { size 8{ 107 {}} }Ag} {} 106.905 092 51.84%
109 109 Ag 109 Ag size 12{rSup { size 8{ 109 {}} }Ag} {} 108.904 757 48.16%
48 Cadmium 114 114 Cd 114 Cd size 12{rSup { size 8{ 114 {}} }Cd} {} 113.903 357 28.73%
49 Indium 115 115 In 115 In size 12{rSup { size 8{ 115 {}} }In} {} 114.903 880 95.7%, ββ size 12{β rSup { size 8{ - {}} } } {} ­ 4 . 4 × 10 14 y 4 . 4 × 10 14 y size 12{4 "." 4 times "10" rSup { size 8{"14"} } y} {}
50 Tin 120 120 Sn 120 Sn size 12{rSup { size 8{ 120 {}} }Sn} {} 119.902 200 32.59%
51 Antimony 121 121 Sb 121 Sb size 12{rSup { size 8{ 121 {}} }Sb} {} 120.903 821 57.3%
52 Tellurium 130 130 Te 130 Te size 12{rSup { size 8{ 130 {}} }Te} {} 129.906 229 33.8%, ββ size 12{β rSup { size 8{ - {}} } } {} ­ 2 . 5 × 10 21 y 2 . 5 × 10 21 y size 12{2 "." 5 times "10" rSup { size 8{"21"} } y} {}
53 Iodine 127 127 I 127 I size 12{rSup { size 8{ 127 {}} }I} {} 126.904 473 100%
131 131 I 131 I size 12{rSup { size 8{ 131 {}} }I} {} 130.906 114 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 8.040 d
54 Xenon 132 132 Xe 132 Xe size 12{rSup { size 8{ 132 {}} }Xe} {} 131.904 144 26.9%
136 136 Xe 136 Xe size 12{rSup { size 8{ 136 {}} }Xe} {} 135.907 214 8.9%
55 Cesium 133 133 Cs 133 Cs size 12{rSup { size 8{ 133 {}} }Cs} {} 132.905 429 100%
134 134 Cs 134 Cs size 12{rSup { size 8{ 134 {}} }Cs} {} 133.906 696 EC, ββ size 12{β rSup { size 8{ - {}} } } {} ­ 2.06 y
56 Barium 137 137 Ba 137 Ba size 12{rSup { size 8{ 137 {}} }Ba} {} 136.905 812 11.23%
138 138 Ba 138 Ba size 12{rSup { size 8{ 138 {}} }Ba} {} 137.905 232 71.70%
57 Lanthanum 139 139 La 139 La size 12{rSup { size 8{ 139 {}} }La} {} 138.906 346 99.91%
58 Cerium 140 140 Ce 140 Ce size 12{rSup { size 8{ 140 {}} }Ce} {} 139.905 433 88.48%
59 Praseodymium 141 141 Pr 141 Pr size 12{rSup { size 8{ 141 {}} }Pr} {} 140.907 647 100%
60 Neodymium 142 142 Nd 142 Nd size 12{rSup { size 8{ 142 {}} }Nd} {} 141.907 719 27.13%
61 Promethium 145 145 Pm 145 Pm size 12{rSup { size 8{ 145 {}} }Pm} {} 144.912 743 EC, αα size 12{α} {} 17.7 y
62 Samarium 152 152 Sm 152 Sm size 12{rSup { size 8{ 152 {}} }Sm} {} 151.919 729 26.7%
63 Europium 153 153 Eu 153 Eu size 12{rSup { size 8{ 153 {}} }Eu} {} 152.921 225 52.2%
64 Gadolinium 158 158 Gd 158 Gd size 12{rSup { size 8{ 158 {}} }Gd} {} 157.924 099 24.84%
65 Terbium 159 159 Tb 159 Tb size 12{rSup { size 8{ 159 {}} }Tb} {} 158.925 342 100%
66 Dysprosium 164 164 Dy 164 Dy size 12{rSup { size 8{ 164 {}} }Dy} {} 163.929 171 28.2%
67 Holmium 165 165 Ho 165 Ho size 12{rSup { size 8{ 165 {}} }Ho} {} 164.930 319 100%
68 Erbium 166 166 Er 166 Er size 12{rSup { size 8{ 166 {}} }Er} {} 165.930 290 33.6%
69 Thulium 169 169 Tm 169 Tm size 12{rSup { size 8{ 169 {}} }Tm} {} 168.934 212 100%
70 Ytterbium 174 174 Yb 174 Yb size 12{rSup { size 8{ 174 {}} }Yb} {} 173.938 859 31.8%
71 Lutecium 175 175 Lu 175 Lu size 12{rSup { size 8{ 174 {}} }Yb} {} 174.940 770 97.41%
72 Hafnium 180 180 Hf 180 Hf size 12{rSup { size 8{ 180 {}} }Hf} {} 179.946 545 35.10%
73 Tantalum 181 181 Ta 181 Ta size 12{rSup { size 8{ 181 {}} }Ta} {} 180.947 992 99.98%
74 Tungsten 184 184 W 184 W size 12{rSup { size 8{ 184 {}} }W} {} 183.950 928 30.67%
75 Rhenium 187 187 Re 187 Re size 12{rSup { size 8{ 187 {}} }Re} {} 186.955 744 62.6%, ββ size 12{β rSup { size 8{ - {}} } } {} 4 . 6 × 10 10 y 4 . 6 × 10 10 y size 12{4 "." 6 times "10" rSup { size 8{"10"} } y} {}
76 Osmium 191 191 Os 191 Os size 12{rSup { size 8{ 191 {}} }Os} {} 190.960 920 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 15.4 d
192 192 Os 192 Os size 12{rSup { size 8{ 192 {}} }Os} {} 191.961 467 41.0%
77 Iridium 191 191 Ir 191 Ir size 12{rSup { size 8{ 191 {}} }Ir} {} 190.960 584 37.3%
193 193 Ir 193 Ir size 12{rSup { size 8{ 193 {}} }Ir} {} 192.962 917 62.7%
78 Platinum 195 195 Pt 195 Pt size 12{rSup { size 8{ 195 {}} }Pt} {} 194.964 766 33.8%
79 Gold 197 197 Au 197 Au size 12{rSup { size 8{ 197 {}} }Au} {} 196.966 543 100%
198 198 Au 198 Au size 12{rSup { size 8{ 198 {}} }Au} {} 197.968 217 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 2.696 d
80 Mercury 199 199 Hg 199 Hg size 12{rSup { size 8{ 199 {}} }Hg} {} 198.968 253 16.87%
202 202 Hg 202 Hg size 12{rSup { size 8{ 202 {}} }Hg} {} 201.970 617 29.86%
81 Thallium 205 205 Tl 205 Tl size 12{rSup { size 8{ 205{}} }Tl} {} 204.974 401 70.48%
82 Lead 206 206 Pb 206 Pb size 12{rSup { size 8{ 206{}} }Pb} {} 205.974 440 24.1%
207 207 Pb 207 Pb size 12{rSup { size 8{ 207{}} }Pb} {} 206.975 872 22.1%
208 208 Pb 208 Pb size 12{rSup { size 8{ 208{}} }Pb} {} 207.976 627 52.4%
210 210 Pb 210 Pb size 12{rSup { size 8{ 210{}} }Pb} {} 209.984 163 α,βα,β size 12{α,β rSup { size 8{ - {}} } } {} ­ 22.3 y
211 211 Pb 211 Pb size 12{rSup { size 8{ 211{}} }Pb} {} 210.988 735 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 36.1 min
212 212 Pb 212 Pb size 12{rSup { size 8{ 212{}} }Pb} {} 211.991 871 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 10.64 h
83 Bismuth 209 209 Bi 209 Bi size 12{rSup { size 8{ 209{}} }Bi} {} 208.980 374 100%
211 211 Bi 211 Bi size 12{rSup { size 8{ 211{}} }Bi} {} 210.987 255 α , β α , β size 12{α,β rSup { size 8{ - {}} } } {} 2.14 min
84 Polonium 210 210 Po 210 Po size 12{rSup { size 8{ 210{}} }Po} {} 209.982 848 α α size 12{α} {} 138.38 d
85 Astatine 218 218 At 218 At size 12{rSup { size 8{ 218{}} }At} {} 218.008 684 α , β α , β size 12{α,β rSup { size 8{ - {}} } } {} 1.6 s
86 Radon 222 222 Rn 222 Rn size 12{rSup { size 8{ 222{}} }Rn} {} 222.017 570 α α size 12{α} {} 3.82 d
87 Francium 223 223 Fr 223 Fr size 12{rSup { size 8{ 223{}} }Fr} {} 223.019 733 α , β α , β size 12{α,β rSup { size 8{ - {}} } } {} 21.8 min
88 Radium 226 226 Ra 226 Ra size 12{rSup { size 8{ 226{}} }Ra} {} 226.025 402 α α size 12{α} {} 1 . 60 × 10 3 y 1 . 60 × 10 3 y size 12{1 "." "60" times "10" rSup { size 8{3} } y} {}
89 Actinium 227 227 Ac 227 Ac size 12{rSup { size 8{ 227{}} }Ac} {} 227.027 750 α , β α , β size 12{α,β rSup { size 8{ - {}} } } {} 21.8 y
90 Thorium 228 228 Th 228 Th size 12{rSup { size 8{ 228{}} }Th} {} 228.028 715 α α size 12{α} {} 1.91 y
232 232 Th 232 Th size 12{rSup { size 8{ 232{}} }Th} {} 232.038 054 100%, αα size 12{α} {} 1 . 41 × 10 10 y 1 . 41 × 10 10 y size 12{1 "." "41" times "10" rSup { size 8{"10"} } y} {}
91 Protactinium 231 231 Pa 231 Pa size 12{rSup { size 8{ 231{}} }Pa} {} 231.035 880 α α size 12{α} {} 3 . 28 × 10 4 y 3 . 28 × 10 4 y size 12{3 "." "28" times "10" rSup { size 8{4} } y} {}
92 Uranium 233 233 U 233 U size 12{rSup { size 8{ 233{}} }U} {} 233.039 628 α α size 12{α} {} 1 . 59 × 10 3 y 1 . 59 × 10 3 y size 12{1 "." "59" times "10" rSup { size 8{3} } y} {}
235 235 U 235 U size 12{rSup { size 8{ 235{}} }U} {} 235.043 924 0.720%, αα size 12{α} {} 7 . 04 × 10 8 y 7 . 04 × 10 8 y size 12{7 "." "04" times "10" rSup { size 8{8} } y} {}
236 236 U 236 U size 12{rSup { size 8{ 236{}} }U} {} 236.045 562 α α size 12{α} {} 2 . 34 × 10 7 y 2 . 34 × 10 7 y size 12{2 "." "34" times "10" rSup { size 8{7} } y} {}
238 238 U 238 U size 12{rSup { size 8{ 238{}} }U} {} 238.050 784 99.2745%, αα size 12{α} {} 4 . 47 × 10 9 y 4 . 47 × 10 9 y size 12{4 "." "47" times "10" rSup { size 8{9} } y} {}
239 239 U 239 U size 12{rSup { size 8{ 239{}} }U} {} 239.054 289 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 23.5 min
93 Neptunium 239 239 Np 239 Np size 12{rSup { size 8{ 239{}} }Np} {} 239.052 933 ββ size 12{β rSup { size 8{ - {}} } } {} ­ 2.355 d
94 Plutonium 239 239 Pu 239 Pu size 12{rSup { size 8{ 239{}} }Pu} {} 239.052 157 α α size 12{α} {} 2 . 41 × 10 4 y 2 . 41 × 10 4 y size 12{2 "." "41" times "10" rSup { size 8{4} } y} {}
95 Americium 243 243 Am 243 Am size 12{rSup { size 8{ 243{}} }Am} {} 243.061 375 α,α, size 12{α,} {} fission 7 . 37 × 10 3 y 7 . 37 × 10 3 y size 12{7 "." "37" times "10" rSup { size 8{3} } y} {}
96 Curium 245 245 Cm 245 Cm size 12{rSup { size 8{ 245{}} }Cm} {} 245.065 483 α α size 12{α} {} 8 . 50 × 10 3 y 8 . 50 × 10 3 y size 12{8 "." "50" times "10" rSup { size 8{3} } y} {}
97 Berkelium 247 247 Bk 247 Bk size 12{rSup { size 8{ 247{}} }Bk} {} 247.070 300 α α size 12{α} {} 1 . 38 × 10 3 y 1 . 38 × 10 3 y size 12{1 "." "38" times "10" rSup { size 8{3} } y} {}
98 Californium 249 249 Cf 249 Cf size 12{rSup { size 8{ 249{}} }Cf} {} 249.074 844 α α size 12{α} {} 351 y
99 Einsteinium 254 254 Es 254 Es size 12{rSup { size 8{ 254{}} }Es} {} 254.088 019 α,βα,β size 12{α,β rSup { size 8{ - {}} } } {} ­ 276 d
100 Fermium 253 253 Fm 253 Fm size 12{rSup { size 8{ 253{}} }Fm} {} 253.085 173 EC, αα size 12{α} {} 3.00 d
101 Mendelevium 255 255 Md 255 Md size 12{rSup { size 8{ 255{}} }Md} {} 255.091 081 EC, αα size 12{α} {} 27 min
102 Nobelium 255 255 No 255 No size 12{rSup { size 8{ 255{}} }No} {} 255.093 260 EC, αα size 12{α} {} 3.1 min
103 Lawrencium 257 257 Lr 257 Lr size 12{rSup { size 8{ 257{}} }Lr} {} 257.099 480 EC, αα size 12{α} {} 0.646 s
104 Rutherfordium 261 261 Rf 261 Rf size 12{rSup { size 8{ 261{}} }Rf} {} 261.108 690 α α size 12{α} {} 1.08 min
105 Dubnium 262 262 Db 262 Db size 12{rSup { size 8{ 262{}} }Db} {} 262.113 760 α,α, size 12{α,} {} fission 34 s
106 Seaborgium 263 263 Sg 263 Sg size 12{rSup { size 8{ 263{}} }Sg} {} 263.11 86 α,α, size 12{α,} {} fission 0.8 s
107 Bohrium 262 262 Bh 262 Bh size 12{rSup { size 8{ 262{}} }Bh} {} 262.123 1 α α size 12{α} {} 0.102 s
108 Hassium 264 264 Hs 264 Hs size 12{rSup { size 8{ 264{}} }Hs} {} 264.128 5 α α size 12{α} {} 0.08 ms
109 Meitnerium 266 266 Mt 266 Mt size 12{rSup { size 8{ 266{}} }Mt} {} 266.137 8 α α size 12{α} {} 3.4 ms
Table A1 Atomic Masses
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