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1 Name Period Nuclear(Chemistry( SpringBreakPacket Due:

2 Name Chemistry 13-1 DIRECTIONS: Watch the assigned video and take notes on this handout. Assigned Video: Nuclear Chemistry: Fusion vs. Fission Nuclear Chemistry - Transmutation - Artificial Transmutation - Fusion - Fission E = mc 2

3 FUSION FISSION

Nuclear Fission and Fusion Model 1. Fission The process of fission occurs when a nucleus splits into smaller pieces.

html) The following equations represent fission reactions, where n = neutron.

60Nd + 81 32Ge + 3 1 0n 2. Fusion Fusion occurs when 2 nuclei join together to form a larger nucleus.

4 Nuclear Fission and Fusion Model 1. Fission The process of fission occurs when a nucleus splits into smaller pieces. Fission can be induced by a nucleus capturing slow moving neutrons, which results in the nucleus becoming very unstable. ( The following equations represent fission reactions, where n = neutron U + 1 0n Ba Kr n U + 1 0n Te Zr n U + 1 0n Sn Mo n U + 1 0n Xe Sr n U + 1 0n Nd Ge n 2. Fusion Fusion occurs when 2 nuclei join together to form a larger nucleus. Fusion is brought about by bringing together two or more small nuclei under conditions of tremendous pressure and heat. (Phillips, Strozak, Wistrom, Glencoe Chemistry p. 766) The following equations represent fusion reactions, where p = proton. 2 1 H + 2 1H 3 1H + 1 1p 3 2 He + 3 2He 4 2He H 2 1 H + 3 1H 4 2He + 1 0n POGIL /5 Written by Michael Fusaro; Assessed by: Rohini Quackenbush, Erin Graham, and Lizabeth Tumminello Edited by Linda Padwa and David Hanson, Stony Brook University

5 Nuclear Fission and Fusion Key Questions 1. What is fission? 2. What is fusion? 3. What is the difference between deuterium,, and tritium,? 4. What quantities are conserved in a nuclear transmutation? 5. The fusion equations show the production of atoms of several different elements, even though each reaction begins with isotopes of hydrogen. Knowing the starting elements, can one predict what element will form as a result of a given reaction? Explain why or why not. 6. The fission equations show the production of many different elements, even though each reaction begins with uranium-235 and one neutron. How is this possible given the conservation laws for nuclear reactions? POGIL /5 Written by Michael Fusaro; Assessed by: Rohini Quackenbush, Erin Graham, and Lizabeth Tumminello Edited by Linda Padwa and David Hanson, Stony Brook University

6 Nuclear Fission and Fusion Exercises 1. An equation in the model shows the fusion of two deuterium nuclei to form a nucleus of tritium. Suggest another product that might form in this reaction. 2 1H + 2 1H 2. Describe how to find the identity of the species X in the equation U + 1 0n Nd + X n. 3. What is missing in the following reaction? U + 1 0n Rb n 4. An atom of U-235 absorbs a neutron and produces an atom of Sb-125 and four neutrons. Identify the other nuclide formed in this reaction. Write the equation to support your answer. 5. Identify the following equations as fission or fusion. 2 1H + 2 1H 3 1H + 1 1p Fission or Fusion? U + 1 0n Ba Kr n U + 1 0n Xe Sr n 3 2He + 3 2He 4 2He H POGIL /5 Written by Michael Fusaro; Assessed by: Rohini Quackenbush, Erin Graham, and Lizabeth Tumminello Edited by Linda Padwa and David Hanson, Stony Brook University

Name Penetrating Power of Particles Chemistry 13-2 ---------------------------------------------------------------------------------------- Directions: Read the text below and answer the questions on

Alpha, beta and gamma radiation can be emitted from any unstable nucleus of an atom. These types of radiation are very different from one another. An alpha particle is essentially a helium nucleus.

7 Name Penetrating Power of Particles Chemistry Directions: Read the text below and answer the questions on the reverse side to show that you understand the text. Alpha, Beta and Gamma Particles In general, there are three main types of radioactive particles. Alpha, beta and gamma radiation can be emitted from any unstable nucleus of an atom. These types of radiation are very different from one another. An alpha particle is essentially a helium nucleus. Under certain conditions, a large nucleus may give off these particles. An alpha particle is two protons and two neutrons. An alpha particle has a positive charge. An alpha particle in isotopic notation looks like this: Alpha particles are very large in comparison to beta and gamma. An alpha particle has very low penetrating ability. People can protect themselves against an alpha particle by using a sheet of paper, which will deflect the alpha particle. Human skin is not affected by alpha particles. However, internal organs that have little to no protection can be harmed by alpha particles. Alpha particles, although easily blocked, can cause a good deal of damage to internal organs because of their size. Therefore, alpha particles are considered ionizing radiation. A beta particle is essentially a free electron. When a beta particle is released, the electron comes flying out of the nucleus. A beta particle has a negative charge. A beta particle in isotopic notation looks like this: Beta particles, which are much smaller than alpha particles, have more penetrating ability. A piece of aluminum foil is required to deflect a beta particle. Beta particles are ionizing radiation, and can penetrate the skin and cause damage to skin and nerve cells. Gamma radiation is produced from the release of pure energy from a nucleus. A gamma ray has no mass and no charge, it is simply a stream of high frequency energy. A gamma particle in isotopic notation looks like this: Gamma rays have no mass, which makes them more difficult to stop. Protection against gamma radiation requires several inches of lead to shield against the radiation. Gamma radiation can travel through every component of the human body, and the radiation when absorbed can cause genetic mutations in living cells. Diagrams of the three particles penetrating ability is shown below:

8 1) Based on the reading and TABLE O, fill in the table below. (I filled some in for you) Particle Notation Charge Mass Penetrating Ability Material that can stop penetration alpha Low ability least hazardous beta -1 Aluminum, layer of clothing gamma 0 2) Which particle has the most penetrating power and is the most hazardous? 3) Which nuclear emission particle has the greatest mass and least penetrating power? 4) Which particle has the least mass and no charge? 5) Which nuclear decay particle consists of energy, only? 6) A scientist found a lead block with a radioactive material inside. The scientist hypothesized that alpha, beta, and gamma radiation were ALL being emitted from a tiny hole in the box. How could the scientist separate each type of radiation? Explain an experimental set-up to separate all three. The diagram below is what the scientist originally found. Thislinerepresentstheradiationconsistingofall threeparticles:alpha,beta,andgamma.howcan theybeseparatedfromeachother?

9 Name Chemistry 13-3 DIRECTIONS: Watch the assigned video and take notes on this handout. Assigned Video: Radioactivity Natural Transmutation 4 Types of Radioactive Decay Modes 1) Alpha Decay 2) Beta Decay 3) Positron Decay 4) Gamma Decay

10 Name Radioactivity Chemistry Directions:(UseyournotesonradioactivityandTableOtohelpanswerthefollowingquestions. 1. Statethenumberofneutronsandprotonsineachofthefollowingnuclei: a. 2 1H : b. 12 6C : 56 Fe : c. 26 d Au : 2. Thethreetypesofradioactiveemissionsarecalledalpha(α),beta(β)andgamma(γ)radiation. Completethetablebelowwiththecorrectinformationabouteachtype. Charge( Symbol(Notation( Can(Be(( Stopped(By( Alpha Beta( Gamma( 3. Whichofthethreeradioactiveemissions(α, β, γ )bestfitthefollowingstatements?writethe correctsymbol/sonthelines. a) Theseemissionsarecharged. b) Thisemissionisthemostmassive(heaviest). c) Thisemissionisthemostcharged. d) Thisemissionismostdangerousoutsideofthebody. e) Thisemissionisstoppedbythinpaperorafewcentimetersofair. f) Thisemissioncantravelthroughpaper,butisstoppedbyaluminum. g) Thisemissioncantravelthroughfairlythicklead.

11 4. Whichtypeofradiation alpha,beta,orgamma: a. Resultsinthegreatestchangeinatomicnumber?Why? b. Resultsintheleastchangeinatomicnumber?Why? c. Producesthegreatestchangeinmassnumber?Why? d. Producestheleastchangeinmassnumber?Why? CHALLENGE!( 5. Completethefollowingnuclearreactions: 226 Ra!??? e a. 88 b Po! Pb +??? c U!??? He d Th! Pa +??? e.??? N! 17 8 O H

12 Name Chemistry 13-5 DIRECTIONS: Watch the assigned video and take notes on this handout. Watch this Video: Half-Life and Radioisotopes Use Table N to look up Half-Lives of radioisotopes. Half-Life Radioisotope Co-60 is used to teat Cancer - Remember because they both start with C I-131 is used to treat Thyroid disorders Remember because both have I C-14 and C-12 are both used in Carbon Dating provides age of very old, once-living things Check out Ed. TED for more explanation:

13 Chemistry: Form WS12.6.1A NUCLEAR CHEMISTRY Name Date Period Working with Half-Life When radioactive materials decay they release high speed particles that bang into other unstable radioactive atoms, hastening their decay. As the process proceeds, the amount of radioactive material decreases. This causes the number of high speed emissions to decrease. The fewer emissions there are, the slower the decay process becomes. As a result, large samples of radioactive material decay at a faster rate than small samples. In fact, as the sample size decreases, the rate of decay slows in such a way that the amount of time it takes for half the sample to decay is constant regardless of the sample size. In other words, it takes 500 g of uranium the same amount of time to decay into 250 g of uranium as it does for 2 g of uranium to decay into 1 g of uranium. The amount of time it takes for a radioactive sample to decay to half its original mass is called the half-life. The easiest way to solve half life problems is to set up a table. Sample Problem How much 42 K will be left in a 320 g sample after 62 h? Step 1: Look up the half life in Table N, the table of Selected Radioisotopes 12.4 h Step 2: Set up a table showing the mass, time elapsed, the fraction remaining, and number of half lives starting with the initial conditions and ending when the full time has elapsed. For each half life elapsed, cut the mass in half, increase the time by an amount equal to the half life, cut the fraction in half, and add one to the number of half lives. Mass Time Fraction Half lives Answer the questions below using data from Table N, the table of Selected Radioisotopes. 1. How long will it take for 30 g of 222 Rn to decay to 7.5 g? ½ / How many grams of 16 N will be left from a 16 g sample after 21.6 s? / / / 32 5 Following this procedure it is possible to determine the final mass, the time elapsed, the fraction of the original sample, or the number of half lives elapsed. Continue

14 Chemistry: Form WS12.6.1A Working with Half-Life NUCLEAR CHEMISTRY Page 2 3. How many half lives will it take for 50 g of 99 Tc to decay to 6.25 g? 4. What fraction of a sample of 32 P will be left after 42.9 d? 5. How long will it take for a 28 g sample of 226 Ra to decay to 3.5 g? 6. How long will it take for 50% of a sample of 131 I to decay? 7. After y, how many grams will be left from a 256 g sample of 232 Th? 8. How long will it take for 500 g of 90 Sr to decay to 125 g? 9. What fraction of a sample of 3 H will be left after y? Evan P. Silberstein, 2003

POGIL: Fission Fusion

Name: Date: Period: Chemistry POGIL: Fission Fusion Why? Up until the 9 s, the only nuclear reactions that had been observed involved nuclei either capturing or emitting small particles such as alpha and