Nam Pr. Atomic Structur/Nuclar Chmistry (Ch. 3 & 21) OTHS Acadmic Chmistry Objctivs: Undrstand th xprimntal dsign and conclusions usd in th dvlopmnt of modrn atomic thory, including Dalton's Postulats, Thomson's discovry of lctron proprtis, Ruthrford's nuclar atom, and Bohr's nuclar atom Us isotopic composition to calculat avrag atomic mass of an lmnt Dscrib th charactristics of alpha, bta, and gamma radiation Dscrib radioactiv dcay procss in trms of balancd nuclar quations Compar fission and fusion ractions. Vocabulary: Isotop, avrag atomic mass, radio-isotop, daughtr nuclus, fission, fusion, half-lif, isotop, nuclar nrgy, nuclar ractions, nuclar sourcs, nuclar wast, radiation, transmutation, positron Topics to rviw: Atomic Structur Scintists & contributions to atomic thory Currnt atomic thory Subatomic particls Ion vs isotop APE MAN calculations Avrag atomic mass calculations Mmoriz: A=P=E M-A=N Alpha particl Bta Particl Providd: Nuclar Chmistry Alpha & bta dcay Alpha, bta, gamma pntranc Fission vs Fusion Half Lif Calculations Priodic tabl CHECKLIST: How to b succssful in OTHS Acadmic Chmistry Pay attntion and tak nots in class Ask qustions in class on matrial that is not clar Work vry pag in th practic packt for th unit Chck answrs to th practic packt onlin at http://othschm.wbly.com/ Com to tutorials with any chmistry tachr Do th onlin homwork and chck solutions onc thy bcom availabl Always do th practic tst for vry tst & ask good qustions on rviw day Kp up with th calndar for th class/b awar of approaching quizzs, tsts, & othr dadlins Us vidos postd on wbsit as a quick and convnint tutorial Rad th chaptr in th book pg1 pg2 pg3 pg pg5 pg6 pg7 pg8 pg9
Nam Pr. Atomic Structur Worksht lpful information: Isotops ar two or mor forms of an lmnt that diffr only in th numbr of nutrons. Atomic numbr is qual to th # of protons, which is th sam as th # of lctrons in any nutral atom (not an ion). Th atomic numbr is found on th priodic tabl; it s th whol numbr. It dfins ach lmnt. Mass numbr is qual to th # of protons + th # of nutrons (p + n) Th mass numbr is diffrnt for ach isotop of an lmnt. It is obtaind from th notation in th lmnt or symbol. For xampl: Carbon-13: mass numbr is 13 13 6 C : mass numbr is 13 (top # is th mass numbr, bottom # is th atomic numbr) Isotop Symbol Atomic Numbr Uranium-235 Mass Numbr # of p + # of n o # of - 3 1 H 2 1 H 1 1 H 29 1 7 7 56 26 Potassium-1 208 82 Pb 81 35 38 50 23 11 Argon-0 19 9 F 32 16 29 3 1
Atomic Structur Worksht Part II: Avrag Atomic Mass Atomic mass is th avrag mass of on atom of an lmnt, in amu. Th atomic mass is found on th priodic tabl; it is th numbr with th dcimal placs. Atomic mass is calculatd by prforming a wightd avrag of th masss of all isotops of an lmnt. 1. Dtrmin th avrag atomic mass for ach of th following lmnts, givn ach isotop s mass and prcnt abundanc. Chck your answrs on th priodic tabl. a. Oxygn, composd of oxygn-16 (mass 15.99 amu and 99.8%), oxygn-17 (mass 17.00 amu and 0.0%), and oxygn-18 (mass 18.00 amu and 0.2%) b. Silvr, composd of silvr-107 (mass 106.91 amu and 51.8%) and silvr-109 (mass 108.90 amu and 8.2%) c. Non, composd of non-20 (mass 19.99 amu and 90.51%), non-21 (mass 20.99 amu and 0.27%), and non-22 (mass 21.99 amu and 9.22%) 2. Dtrmin th avrag atomic mass for this unknown lmnt, and thn us th priodic tabl to idntify th lmnt: Isotop #1 has mass 3.97 amu and % abundanc 75.77%. Isotop #2 has mass 36.97 amu and % abundanc 2.23%. Th lmnt is: 3. Boron has 2 isotops: boron-10 (mass 10.0 amu) and boron-11 (mass 11.0 amu). Look up th avrag atomic mass of boron on th priodic tabl: Find th prcnt abundanc of ach isotop. Hint: Call th rlativ abundanc for on isotop x, and thn th rlativ abundanc of th othr isotop is 1-x. 2
Nuclar Chmistry Pr- Tst Tru or Fals? 1. Hom smok dtctors contain radioactiv matrials. 2. Radioactiv matrials and radiation ar unnatural; thy did not xist on Earth until cratd by scintists. 3. All radiation causs cancr.. You can gt cancr from a microwav. 5. Human snss can dtct radiation. 6. Individuals vary widly concrning how thy ar affctd by xposur to radiation. 7. Small amounts of mattr chang to immns quantitis of nrgy rlasd by nuclar wapons. 8. Physicians can distinguish cancr causd by radiation xposur from cancr rsulting from othr causs. 9. Mdical x-rays ar dangrous. 10. Nuclar powr plants crat srious hazards to public halth and to th nvironmnt. 11. An improprly opratd nuclar powr plant can xplod lik a nuclar wapon. 12. Som nuclar wasts must b stord for cnturis to prvnt dangrous radioactivity from scaping. 13. Nw dangrous lmnts ar bing invntd vry day. 1. Nuclar powr plants produc matrial that can b convrtd into nuclar wapons. 15. All nuclar mdical tchniqus ar highly dangrous. 3
Nam: Alpha and Bta Dcay Ractions Practic Priod: Writ a balancd quation for ach of th following nuclar ractions. Exampl Chlorin-36 dcays by bta mission. Dubnium-262 dcays by alpha mission 36 36 0 262 258 Cl Ar+ Db Lr 17 18 1 105 103 + 2 1. Krypton-87 dcays by bta mission. 2. Curium-20 dcays by alpha mission. 3. Uranium-232 dcays by alpha mission.. Silicon-32 dcays by bta mission. 5. Zinc-71 dcays by bta mission. 6. Amricium-23 dcays by alpha mission. 7. Cobalt-60 dcays by bta mission. 8. Phosphorus-32 dcays by bta mission. 9. Gadolinium-150 dcays by alpha mission. 10. Lad-210 dcays by mitting both a bta and an alpha particl.
Nam: Priod: Radioactiv Dcay Sris Using th information givn hr as wll as th priodic tabl and your knowldg of alpha (α) and bta (β) dcay ractions complt ach of th following. a. Labl ach raction as an alpha or bta dcay on th blank in front of th numbr. b. Complt ach raction and us your answr from on raction as th ractant for th nxt stp. This is th dcay sris of Uranium-238. 1. 92 U + 238 23 90 (a) Th 8. (g) (h) 2. 0 90 Th 1+ 23 23 91 (a) (b) Pa 9. (h) 0 1 (i) 3. 23 91 (b) 0 Pa 1 (c) 10. (i) 0 1 (j). (c) (d) 11. (j) (k) 5. (d) 2 () 12. (k) 0 1 (l) 6. () (f) 13. (l) 0 1 (m) 7. (f) (g) 1. (m) (n) 5
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Half-lif Worksht Fill in th missing information; show work blow using ithr th formula or th chart mthod. Tim units in first 2 columns must match! Convrt whn ncssary. Half-lif Elapsd tim Initial amount Amount rmaining 1. 90 min. 6 hours 3000 mg 2. 300 yars 600 yars 27.6 g 3. 9 months 3 yars 10,000 g. 1 yar 1 yar 526 g 5. 235 yars 705 yars 20 g 6. 35 yars 10 yars 10 g 7. 800 yars 1600 g 100 g 8. 18 hours 3 days 500 g 9. 5 min. 30 min. 60 g 10. 2000 yars 6000 yars 8000 g 11. 23 hours 92 hours 12,000 g 12. 90 s 6 min. 3 g 13. 7 yars 9 yars 1 g 1. 8 billion yars 1000 g 250 g 15. 2 hours 5820 g 2910 g 16. 2000 yars 60 g 20 g 17. days 2800 g 700 g 18. hours 1 day 600 g 8
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