1

Chapter 9: Nuclear ChemistryChapter 9: Nuclear Chemistry

RadioactivityRadioactivityNuclear EquationsNuclear Equations

Radiation DetectionRadiation DetectionHalf-LifeHalf-Life

Medical ApplicationsMedical ApplicationsFission & FusionFission & Fusion

2

Isotopes of HydrogenIsotopes of HydrogenIsotopes =Isotopes = Atoms of the same element but

having different masses.11

21

31H H H

++--

++--

++--

Protium99.99%99.99%

Deuterium0.01%0.01%

TritiumTrace %Trace %

Average Atomic weightAverage Atomic weight of Hydrogen = 1.007941.00794 amuamu

3

Isotopes of CarbonIsotopes of Carbon

Average Atomic weightAverage Atomic weight of C= 12.01112.011 amuamu

98.89%98.89%

CC661212 CC66

1313 CC661414

1.11%1.11% Trace %Trace %

++++

++++++ ++

--

--

----

----

--

++++

++++++ ++

--

---- --

--++

++++++

++ ++

--

--

--

----

--

4

Radioactive IsotopesRadioactive Isotopes

CC661414

++++

++++++ ++

--

--

--

----

--++

31 H --

Nucleus is unstableSo falls apart (decays)

Giving radioactive particles

Hydrogen-3Carbon-14

5

Radioactive Isotopes in MedicineRadioactive Isotopes in Medicine

TcTc434399m99m

123123 5353 II

131131 5353 II

60602727 CoCo

Diagnose thyroid functionDiagnose thyroid function

Treat hyperthyroid Treat hyperthyroid (destroys cells)(destroys cells)

Destroy tumors Destroy tumors (( radiation) radiation)

Diagnose bone, tissue Diagnose bone, tissue (most common)(most common)

6

Alpha DecayAlpha Decay

PbPb8282206206 ++

++++++

++ ++

2102108484 Po

4422 HeHe ++ ++

ParticleParticle

2102108484 Po PbPb8282

206206 + 4422 HeHe

7

Beta DecayBeta Decay

NN771414

141466 CC

00-1-1ee --

ParticleParticle++

++

++++++ ++ ++

++++++

++ ++++

+ -+ -

1100 nn 11

11 HH +00-1-1ee

neutron proton electron

8

Beta DecayBeta Decay

NN771414

141466 CC

00-1-1ee --

ParticleParticle++

++

++++++ ++ ++

++++++

++ ++++

+ -+ -

+ 00-1-1ee1414

66 CC NN771414

9

Gamma DecayGamma Decay

99m99m4343 TcTc decaydecay

++++

++++++ ++ ++

++++++

++ ++

99994343 TcTc

+99m99m4343 TcTc TcTc4343

9999

10

11

Ionizing RadiationIonizing Radiation

O HH O HH

--Radiation knocks off an electron

An ion

C HH

H

HC HH

H

H

A radicalIons & radicals cause damaging chain reactions

12

Geiger CounterGeiger Counter

--Radiation knocks off

an electron

An ion

Ions detected by Counter

ArArGas in

instrument tube

13

14

Radiation: Penetration through AirRadiation: Penetration through Air

++ ++

--

4 cm4 cm

6-300 cm6-300 cm

400 m400 m

15

++ ++

--

Tissue Penetration DepthTissue Penetration Depth

0.05 mm0.05 mm

0.06-5 mm0.06-5 mm

>50 cm>50 cm

16

Radiation: ShieldingRadiation: Shielding

++ ++

--

Paper Paper ClothCloth

Heavy Heavy ClothCloth

Pb, thick Pb, thick concreteconcrete

17

Nuclear EquationsNuclear Equations

2262268888 Ra RnRn8686

222222 + 4422 HeHe

Radon gas in BuildingsRadon gas in Buildings

PoPo8484218218 + 44

22 HeHe

Gas

18

1311315353 I XeXe5454

131131 + 00-1-1ee

Thyroid check & treatmentThyroid check & treatment

Cancer TreatmentCancer TreatmentNuclear EquationsNuclear Equations

60602727 Co NiNi2828

6060 + 00-1-1ee

19

Radiation DetectionRadiation Detection

1 Ci = 3.7 x 1010disintegrations sec

1 Bq = 1 disintegration sec

# of disintegrations by of 1g Ra

ActivityActivity

Becquerel (Bq)Becquerel (Bq)

Curie (Ci)Curie (Ci):

20

Radiation DetectionRadiation Detection

Absorbed DoseAbsorbed Dose

21

++ ++

--

Tissue Penetration DepthTissue Penetration Depth0.05 mm0.05 mm

0.06-5 mm0.06-5 mm

>50 cm>50 cm

Radiation Absorbed Dose (Rad) (D)Radiation Absorbed Dose (Rad) (D): 1 rad = 1 rad = 1 x 101 x 10-2-2 JJ

kg tissuekg tissue1 rad = 1 rad = 2.4 x 102.4 x 10-3 -3 calcal

kg tissuekg tissue

Radiation Detection: Biological EffectRadiation Detection: Biological Effect

22

++ ++

--

Tissue Penetration DepthTissue Penetration Depth

0.05 mm0.05 mm

0.06-5 mm0.06-5 mm

>50 cm>50 cm

Radiation Absorbed Dose (Rad) (D)Radiation Absorbed Dose (Rad) (D): 1 Gray = 1 Gray = 1 J1 J

kg tissuekg tissue100 rad = 1 Gray100 rad = 1 Gray

23

Radiation DetectionRadiation Detection

Biological Damage Biological Damage

24

Radiation Equivalent for Man (rem)Radiation Equivalent for Man (rem)

1 Rem1 Rem = 1 Rad x RBERBE relative biological effectivenessrelative biological effectiveness

RBERBE2020

11

11

25

Annual Radiation Exposure in USAAnnual Radiation Exposure in USA

Ground = 15 mrem

Air, HAir, H22O, Food = 30 mremO, Food = 30 mremCosmic = 40 mremCosmic = 40 mrem

Wood,concrete,bricks = 50 mremWood,concrete,bricks = 50 mrem

X-rays: X-rays: Chest = 50 mremChest = 50 mremDental = 20Dental = 20

SmokingSmoking = 35 mrem

TV = 2 mrem

Radon = 200 mremRadon = 200 mrem

Total = 170 mrem / yrTotal = 170 mrem / yr

26

Biological Effects of RadiationBiological Effects of RadiationDose in rem (at one time)Dose in rem (at one time)0-250-25 genetic damage possible but genetic damage possible but usually undetectedusually undetected

25-10025-100 decrease # of white blood decrease # of white blood cells (temporary)cells (temporary)

100-200100-200 mild radiation sickness mild radiation sickness (vomit, diarrhea, strong decrease # (vomit, diarrhea, strong decrease # white blood cells)white blood cells)

>300>300 (diarrhea, hair loss, infection) (diarrhea, hair loss, infection)

500500 LDLD50 50 for humansfor humans

27

300 300 LDLD50 50 for dogsfor dogs

800 800 LDLD50 50 for ratsfor rats

50,000 LD50,000 LD50 50 for Bacteriumfor Bacterium

100,000 LD100,000 LD50 50 for Insectsfor Insects

Biological Effects of RadiationBiological Effects of RadiationDose in remDose in rem

500500 LDLD50 50 for humansfor humans

28

4,500 4,500 LymphomaLymphoma

5,000 – 6,0005,000 – 6,000 Skin cancer Skin cancer6,000 6,000 Lung cancerLung cancer6,000 – 7000 6,000 – 7000 Brain TumorBrain Tumor

Therapeutic Doses of RadiationTherapeutic Doses of RadiationDose in remDose in rem

29

FDA approved killing of bacteria with:

0.3 – 1 kGy ionizing radiation from

Co-60 or Cs-137(gamma producers) Strawberries left on counter for 2 weeks.

The irradiated berries on right show no spoilage.

30

Half-LifeHalf-Lifett1/21/2 = Time for 1/2 sample to decay = Time for 1/2 sample to decay

1311315353 I

20 g

tt1/21/2 = =

8 days8 days10 g

8 days8 days

5 g

31

rays image Shows blood flow

BB551111

111166 CC

00+1+1ee ++

Positron Emission Tomography (PET)Positron Emission Tomography (PET)

PositronPositron++

++++

++ ++++00

++++

++++ ++

00

111155 BB

111166 CC +

00+1+1

eepositron

00-1-1 eeelectronelectron

raysraysDetectableDetectable

--

32

PET ScansPET Scans

Normal Alzheimer's

33

34

Known in Britain by the trade name ‘Pedoscope’. The machine produced an X-ray of the customer’s foot inside a shoe to ensure shoes fitted accurately, which both increased the wear-time of the shoe and with that, the reputation of the shoe shop.The customer placed their foot over an X-ray tube contained within the wooden base of the Pedoscope. From this, a beam of X-rays passed through the foot and cast an image onto a fluorescent screen above. The screen could be observed via three viewing points – one for the shoe-fitter, one for the customer, and one for a third party (usually the guardian of a child being fitted). The accommodation for three viewing points may seem a little extravagant, but it may be an indication of the popularity of the Pedoscope and the interest the public had in the machine.

35

36

Shoe-Fitting Fluoroscope (ca. 1930-1940)Shoe-Fitting Fluoroscope (ca. 1930-1940)

Basic Description The shoe fitting fluoroscope was a common fixture in shoe stores during the 1930s, 1940s and 1950s. A typical unit, like the Adrian machine shown here, consisted of a vertical wooden cabinet with an opening near the bottom into which the feet were placed. When you looked through one of the three viewing ports on the top of the cabinet (e.g., one for the child being fitted, one for the child's parent, and the third for the shoe salesman or saleswoman), you would see a fluorescent image of the bones of the feet and the outline of the shoes.

37

38

FissionFission

23592 U

10n 236

92 U

+

9136Kr

14256Ba

unstable

Splitting atoms for Energy

Uses:Uses:•Atomic BombAtomic Bomb•Nuclear PowerNuclear Power

39

FissionFission

Need critical masscritical mass of U-235 to sustain chain reaction to produce enough Energy for an explosion

40

U-235U-235

FissionFission

Nuclear Power plants: •Controlled fission •avoids critical mass

41

41

Uranium is the fuel of the nuclear power plant in the US.  However, we can not just dump uranium into the core like we shovel coal into a furnace.  The uranium must be processed and formed into fuel pellets, which are about the size of a pencil eraser.  The fuel pellets are then stacked inside hollow metal tubes to form fuel rods.  Fuel rods are 11 to 25 feet in length.  Each UO2 pellet has the energy equivalent to burning 136 gal of oil, 2.5 tons of wood, or 1 ton of coal.

Uranium oxide pellet used in nuclear fuel rods.

42

43

44

44

Trojan Nuclear Power Plant – Rainier, Oregon

45

May 21, 2006

46

46

Trojan Nuclear Reactor– Rainier, Oregon

48

Yucca Mountain in Nevada – site for nuclear depository?

49

1. Canisters of waste, sealed in special casks, are shipped to the site by truck or train.

2. Shipping casks are removed, and the inner tube with the waste is placed in a steel, multilayered storage container.

3. An automated system sends storage containers underground to the tunnels.

4. Containers are stored along the tunnels, on their side.

Conceptual Design of Yucca Mountain Disposal Plan

50

51

Pros Department of Energy (DOE) In a desert location Isolated away from population centers (Las Vegas, the

nearest metropolitan area, is 90 miles away) Secured 1,000 feet under the surface In a closed hydrologic basin Surrounded by federal land Protected by natural geologic barriers Protected by robust engineered barriers and a flexible

design

52

Cons: Nevada's Agency for Nuclear Projects

Yucca's location in an active seismic (earthquake) region

the presence of numerous earthquake faults (at least 33 in and around the site) and volcanic cinder cones near the site

the presence of pathways (numerous interconnecting faults and fractures) that could move groundwater (and any escaping radioactive materials) rapidly through the site to the aquifer beneath and from there to the accessible environment.

evidence of hydrothermal activity within the proposed repository block

53

Putting end to Yucca Mountain project Putting end to Yucca Mountain project ‘within reach,’ state commission says‘within reach,’ state commission says

Jan. 21, 2013

http://www.lasvegassun.com/news/2013/jan/21/putting-end-yucca-mountain-project-within-reach-st/