RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 WORKSHEET #. worker accideally igesed oe millicurie of I3. I3 has a half-life of 8 days. How may disiegraios per secod of I3 are i he workers body afer 5 days? How may dpm would here be afer 430 days if i were riium wih a -year half-life?. sample of I3 (half-life = 8 days) is kep for 80 days, a which ime he aciviy is microcurie. Wha was he origial aciviy? 3. If a sample of wood has goe hrough 4 half lives of carbo-4. The half-life of Carbo- 4 is 5740 years. a. How old is he wood? b. Wha perce of he origial carbo-4 remais i he wood? c. Wha perce of he origial carbo-4 has decayed from he wood? 4. paricular uclide has a half-life of 3 years. I has bee o sie for 4 mohs. How may half-lives has i bee hrough sice i came o sie?
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay 5. paricular uclide has bee o sie for 456 days. I has bee hrough 0.876 radioacive half-lives. Wha is is half-life? 6. paricular uclide has bee here for 4 mohs i has bee hrough 6 half lives. Wha is is half-life? 7. gamma specroscopy source coais.05 uci of Cd09 whe ew. I order for he source o remai usable, i mus have a Cd09 aciviy of 0.65 uci. How log ca he source be used before eedig replaceme? 8. Na4 is produced durig euro irradiaio of a produc. The produc is o safe o hadle uil 55 hours has elapsed ad he aciviy has decayed o 7 uci. Wha is is iiial aciviy? 9..0 Ci Ir-9 source has decayed by 7.6% sice is maufacure. How log has i bee sice is maufacure?
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 WORKSHEET # KEY. = o = mci 5 days 8 days = 0.648 mci dpm dps X dps = 0.648 mci.e09 =.40E07 dps mci 60 dpm. = o f = o µ Ci = o =.0E03 µ Ci 80 days 8 days 3. a. 5740 years half life 4 half lives =.30E04 years b. 6.5 % c. 93.75 % 4. 4 mohs = = 0.389 half lives 36 mohs 5. = 456 days = = 50.5 days 0.876 6. = 4 mohs = = 0.667 mohs or 0 6 half lives days 3
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay 7. = o = f log o = log 0.5 0.65 log.05 log 0.5 = = 0. 69887 0.69887 46 days = = 39.6 days = 8. = o f = o 7 µ Ci = o = 7.7 µ Ci 55 hours 4.95 hours 9. = o f log o log 0.5 = 0.73848 log.0 log 0.5 = = 0.4659 = 0.4659 73.83 days = = 34.40 days = 4
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 WORKSHEET # pilo-pla food irradiaor is beig buil o es he feasibiliy of cosrucig a larger faciliy. The food will pass by a ushielded Co-60 poi source o a coveyer bel a a cosa speed ad disace. The food will be exposed for a oal ime of 50 miues a a disace of 6 fee from he source. The pla was o operae for 4 years wihou alerig he disace, coveyor speed or source aciviy. Each aricle of food mus receive a leas 500 Rad, bu o more ha 000 Rad. I addiio, he source mus be reraced io a lead shield for maieace eries. The shield mus reduce he dose rae o 00 mrem/hr or less a fee from he source. Co-60 daa Half life (½) = 5.7 years Two ( emissios:.33 Mev 00%.7 Mev 00% Shieldig value for lead: HVL = 0.60 TVL =.0. Wha is he miimum ad maximum curie coe rage for he source?. Wha is he miimum hickess (i iches) for he lead shield? 5
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 WORKSHEET # KEY. miimum curie coe = 437 ci (crieria is havig 440 ci whe source is 4 yrs old o give 500 Rad/50 miues) maximum curie coe = 880 ci (crieria is o exceedig 000 Rad/50 miues whe source is ew). miimum lead hickess = 0.07 iches (crieria is maximum curie coe of 880 ci) 6
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 WORKSHEET #3 crucial piece of safey equipme is calibraed everyday a 8:00 M usig a Ir9 source (half life = 78.83 days). By procedure, he source mus have a aciviy 30,000 dpm, ad 50,000 dpm. midigh (0000) March, 003; he source aciviy was 35,000 dpm. (use a leas decimals i all calculaios). O wha dae ad ime (o he eares hour) will he source become uusable?. I akes e days for a ew source o arrive from he maufacurer afer beig ordered. Your maager was he ew source o arrive o he same day ha he old source becomes uusable. Whe should you order i? 3. Your maager also was he source o be usable he day i arrives, ye sill ge he absolue maximum useful life spa ou of i. How much aciviy should you order o he source? 4. While you are o he phoe wih he source maufacurer sales rep., hey iform you ha hey ca oly process requess i uis of ηci. How much should you order? 5. Wha is he oal usable life spa of he ew source (days, hours, miues)? 7
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 QUIZ. mog sable isoopes, as he umber of proos icreases, how does he euro/proo raio chage? a. Remais o b. pproaches o.5 c. pproaches.5 o d. No predicable red. The propery of cerai uclides o spoaeous emi radiaio is called wha? a. Nuclear isabiliy b. Radioaciviy c. Fissio d. Half life 3. The process by which a ucleus spoaeously disiegraes by oe or more discree eergy seps uil a sable sae is reached is called wha? a. Gamma decay b. lpha decay c. Bea mius decay d. Radioacive decay 4. Why are fissio producs usable? a. Too large a proporio of euros o mass defec b. Too large a proporio of proos o mass defec c. Too large a proporio of euros o proos d. Too large a proporio of proos o euros 5. Curre regulaios defie he curie (Ci) as wha? a. 3.7 E 0 dps b. 3.7 E 0 dpm c.. E Bq d.. E dps 8
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay 6. Wha is he defiiio of oe becquerel (Bq)? a. dps b. dpm c. 3.7 E 0dpm d.. E dps 7. Wha is he erm used o describe he aciviy per ui mass? a. Decay cosa b. Specific aciviy c. N : P raio d. Gram aomic mass 8. "Exposure" (X) is a measure of ioizaio produced i air by wha ype of radiaio? a. Gamma b. Pariculae c. y ype d. Gamma ad X-ray 9. Wha are he uis of "bsorbed Dose" (D)? a. Rad b. Roege c. Rem d. Ergs 0. Wha are he uis of "Dose Equivale" (H)? a. Curie b. Gray c. Becquerel d. Siever 9
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay. "Qualiy Facor" (Q) is used o relae wha wo quaiies? a. omic mass uis o Mev per ucleo b. Eglish uis o SI uis c. bsorbed dose o biological damage d. Becquerel o disiegraio per miue. Oe Rem is equal o how may sievers (Sv)? a..0 Sv b. Sv c. 00 Sv d.. Sv 3. 3.7 E 0 gray (Gy) is equal o how may Rad? a. 3.7 E Rad b..0 E Rad c..7 E - Rad d.. E 0 Rad 4. Lis wo aspecs associaed wih he decay of a radioacive uclide? 5. O wha page i he Char of he Nuclides will you fid a figure depicig he hree aurally occurrig radioacive decay chais? 6. Usig oly he mos promie decay mode, wha is he sable ed produc of Pu 4? 7. Ideify he followig decay mode: X Y + β v Z Z+ + 8. Wha is he omic Number of u98? 0
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay 9. Wha is he mos promie decay mode of Pa7.? 0. Wha is he gamma decay eergy of Bi08 i uis of Mev?. Wha is he half life of Ni66? (Iclude uis.). How may euros does Pm43 have? 3. Complee he followig char. Radiaio Symbol Pariculae Y or N Charge lpha Bea mius Gamma 4. Calculae he half life: Exacly 3 hours ago, a radioacive sample measured 5 ηci of aciviy. Now i measures 4 pci of aciviy. Wha is he half life of he sample (i uis of miues)? Show all work.
RCT Workshees/Quizzes.06 Radioaciviy ad Radioacive Decay.06 QUIZ KEY. c. b 3. d 4. c 5. a 6. a 7. b 8. d 9. a 0. d. c. a 3. a 4. Mode of decay or eergies of emissios; ypes of emissios or rae of decay 5. Page 6. 09 Bi 7. Bea mius 8. 79 9. lpha decay 0..644 MeV. 54.6 hours. 8 3. Radiaio Symbol Pariculae Y or N Charge lpha α Y + Bea mius β - Y - Gamma γ N 0 4. 50 miues