differentiating chemical reactions from nuclear reactions 1

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  • Slide 1
  • Differentiating Chemical Reactions from Nuclear Reactions 1
  • Slide 2
  • CHEMICALNUCLEAR Occurs when bonds are broken or formed. Occurs when nuclei emit particles and/or rays. Atoms remained unchanged, though may be rearranged. Atoms often converted into atoms of another element. Involves valence electronsMay involve protons, neutrons or electrons Small energy changesHUGE energy changes Reaction rates affected by temp and pressure Reaction rate NOT normally affected temp and pressure
  • Slide 3
  • CHEMICALNUCLEAR Occurs when bonds are broken or formed. Occurs when nuclei emit particles and/or rays. Atoms remained unchanged, though may be rearranged. Atoms often converted into atoms of another element. Involves valence electronsMay involve protons, neutrons or electrons Small energy changesHUGE energy changes Reaction rates affected by temp and pressure Reaction rate NOT normally affected temp and pressure
  • Slide 4
  • CHEMICALNUCLEAR Occurs when bonds are broken or formed. Occurs when nuclei emit particles and/or rays. Atoms remained unchanged, though may be rearranged. Atoms often converted into atoms of another element. Involves valence electronsMay involve protons, neutrons or electrons Small energy changesHUGE energy changes Reaction rates affected by temp and pressure Reaction rate NOT normally affected temp and pressure
  • Slide 5
  • CHEMICALNUCLEAR Occurs when bonds are broken or formed. Occurs when nuclei emit particles and/or rays. Atoms remained unchanged, though may be rearranged. Atoms often converted into atoms of another element. Involves valence electronsMay involve protons, neutrons or electrons Small energy changesHUGE energy changes Reaction rates affected by temp and pressure Reaction rate NOT normally affected temp and pressure
  • Slide 6
  • CHEMICALNUCLEAR Occurs when bonds are broken or formed. Occurs when nuclei emit particles and/or rays. Atoms remained unchanged, though may be rearranged. Atoms often converted into atoms of another element. Involves valence electronsMay involve protons, neutrons or electrons Small energy changesHUGE energy changes Reaction rates affected by temp and pressure Reaction rate NOT normally affected temp and pressure
  • Slide 7
  • CHEMICALNUCLEAR Occurs when bonds are broken or formed. Occurs when nuclei emit particles and/or rays. Atoms remained unchanged, though may be rearranged. Atoms often converted into atoms of another element. Involves valence electronsMay involve protons, neutrons or electrons Small energy changesHUGE energy changes Reaction rates affected by temp and pressure Reaction rate NOT normally affected temp and pressure
  • Slide 8
  • Write a multiple-choice test question for the previous chart.
  • Slide 9
  • 9 Nuclear Radiation Natural Radioactivity A person working with radioisotopes wears protective clothing and gloves and stands behind a shield.
  • Slide 10
  • Radioactivity Any process where the nucleus emits particles or energy
  • Slide 11
  • 11 Unstable nucleus.
  • Slide 12
  • 12 Radioactive Isotopes A radioactive isotope has an unstable nucleus emits radiation to become more stable can be one or more isotopes of an element is written with a mass number and an atomic number includes the mass number in its name Example: iodine-131
  • Slide 13
  • 13 Examples of Radioactive Isotopes
  • Slide 14
  • 14 Learning Check Thallium-201 is used for heart scans to determine cardiac function. A. How many protons are in thallium-201? B. How many neutrons are in thallium-201? C. What is the atomic symbol of thallium-201?
  • Slide 15
  • 15 Nuclear Radiation Nuclear radiation is the radiation emitted by an unstable atom takes the form of alpha particles, neutrons, beta particles, positrons, or gamma rays A representation of a Geiger-Mller counter
  • Slide 16
  • 16 Alpha Particle An alpha ( ) particle has a helium nucleus 2 protons and 2 neutrons a mass number of 4 a charge of 2+ a low energy compared to other radiation particles
  • Slide 17
  • 17 Beta Particle A beta ( ) particle is a high-energy electron has a mass number of 0 has a charge of 1- forms in an unstable nucleus when a neutron changes into a proton and an electron
  • Slide 18
  • 18 Positron A positron ( + ) has a mass number of 0 has a charge of 1+ forms in an unstable nucleus when a proton changes into a neutron and a positron
  • Slide 19
  • 19 Gamma ( ) Ray A gamma ( ) ray is high-energy radiation has a mass number of 0 has a charge of 0 is emitted from an unstable nucleus to give a more stable, lower energy nucleus
  • Slide 20
  • 20 Summary of Common Forms of Nuclear Radiation
  • Slide 21
  • 21 Learning Check Give the mass number and charge of each type of radiation. 1. alpha particle 2. positron 3. beta particle 4. neutron 5. gamma ray
  • Slide 22
  • 22 Radiation protection requires paper and clothing for alpha particles a lab coat or gloves for beta particles a lead shield or a thick concrete wall for gamma rays limiting the amount of time spent near a radioactive source increasing the distance from the source Radiation Protection
  • Slide 23
  • How Far Away? Inverse Square Law Write a multiple choice test question over this topic!
  • Slide 24
  • 24 Radiation and Shielding Required
  • Slide 25
  • 25 Radiation Protection Different types of shielding are needed for different radiation particles. Radioactive particles/rays vary greatly in penetrating power.
  • Slide 26
  • 26 Learning Check Indicate the type of radiation (alpha, beta, and/or gamma) protection for each type of shielding. 1) heavy clothing 2) paper 3) lead 4) lab coat 5) thick concrete A person working with radioisotopes wears protective clothing and gloves and stands behind a shield.
  • Slide 27
  • 27 Nuclear Radiation Nuclear Equations A radon gas detector is used to determine radon levels in buildings with inadequate ventilation.
  • Slide 28
  • Radioactive Decay In radioactive decay, a nucleus spontaneously emits radiation a nuclear equation is written for the radioactive nucleus, the new nucleus, and the radiation emitted Radioactive nucleus new nucleus + radiation ( , , , + ) 28
  • Slide 29
  • 29 In a nuclear equation, the type of radiation emitted causes changes in the mass numbers changes in the atomic numbers for the nuclei of the unstable and stable nuclei Nuclear Equations
  • Slide 30
  • 30 In a balanced nuclear equation, the sum of the atomic numbers for the nuclei of the reactant and the products must be equal Mass Numbers Total = 238 = 238 Total = 92 = 92 Atomic Numbers Balancing Nuclear Equations
  • Slide 31
  • 31 Guide to Completing a Nuclear Equation
  • Slide 32
  • 32 Alpha Decay In alpha decay, a radioactive nucleus emits an alpha particle to form a new nucleus that has a mass number 4 less than that of the initial nucleus an atomic number that has decreased by 2 from that of the initial nucleus
  • Slide 33
  • 33 Example of Writing an Equation for Alpha Decay Write an equation for the alpha decay of STEP 1 Write the incomplete nuclear equation. STEP 2 Determine the missing mass number. 222 = ? + 4 222 4 = 218 218 = ? (mass number of new nucleus)
  • Slide 34
  • 34 Equation for Alpha Decay (continued) STEP 3 Determine the missing atomic number. 86 = ? + 2 86 2 = ? 84 = ? (atomic number of new nucleus STEP 4 Determine the symbol of the new nucleus. Symbol of element 84 = Po STEP 5 Complete the nuclear equation.
  • Slide 35
  • 35 Beta Decay Beta decay occurs when an electron (beta particle) is emitted from the nucleus a neutron in the nucleus breaks down
  • Slide 36
  • 36 Write an equation for the beta decay of potassium-42. STEP 1 Write the incomplete nuclear equation. STEP 2 Determine the missing mass number. 42 = ? + 0 42 0 = 42 = ? (mass number of new nucleus) STEP 3 Determine the missing atomic number. 19 = ? 1 19 + 1 = ? 20 = ? (atomic number of new nucleus) Writing an Equation for a Beta Emitter
  • Slide 37
  • 37 STEP 4 Determine the symbol of the new nucleus. Symbol of element 20 = Ca STEP 5 Complete the nuclear equation. Writing an Equation for a Beta Emitter (continued)
  • Slide 38
  • 38 Write the nuclear equation for the beta decay of Xe-133. Learning Check
  • Slide 39
  • 39 In positron emission, a proton is converted to a neutron and a positron the mass number of the new nucleus is the same, but the atomic number decreases by 1 Positron Emission
  • Slide 40
  • 40 Write the nuclear equation for the positron emission by Rb-82. Learning Check
  • Slide 41
  • 41 In gamma radiation, energy is emitted from an unstable nucleus, indicated by m following the mass number the mass number and the atomic number of the new nucleus are the same Gamma ( ) Radiation
  • Slide 42
  • 42 Summary of Types of Radiation
  • Slide 43
  • 43 Producing Radioactive Isotopes Radioact

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