Unit 7Unit 7Nuclear ChemistryNuclear Chemistry

ByByKevin “KG” Gerber Ding and Kevin “KG” Gerber Ding and

Steven “The Flash” HougSteven “The Flash” Houg

Radioactive DecayRadioactive Decay

α-particleββ -particle -particleγγ-ray-ray

The Alpha ParticleThe Alpha Particle

• α or He• Largest of the 3 radioactive

particles• Lowest penetrating ability Sample Decay:Sample Decay:

U U α + Th

42

42

42

23592

23190

The Beta ParticleThe Beta Particle

oror Same electrical charge and Same electrical charge and

mass as an electronmass as an electron Sample Decay:Sample Decay:

N N OO + + ee

e 0-1

0-1β

0-1

13 8

13 7

Gamma RaysGamma Rays

YY

Gamma rays are photonsGamma rays are photons They have no mass and no They have no mass and no

chargecharge

00

Positron EmissionPositron Emission

oror Positrons are equivalent to Positrons are equivalent to

positively charged electrons or positively charged electrons or positively charged beta particlespositively charged beta particles

Formed when a neutron splits Formed when a neutron splits into a neutron and another into a neutron and another particle (positron)particle (positron)

p e + np e + n

0+1e β 0

+1

0+1

10

11

Electron CaptureElectron Capture

Occurs when an electron is captured Occurs when an electron is captured by the nucleusby the nucleus

e + p ne + p n 0 -1

1+1

10

Radioactive Decay SeriesRadioactive Decay Series

238 92U 4

2α +234 90T

h+β 0

-1234 91Pa +β 0

-1234 92U +4

2α

234 90T

h234 91Pa234 92U230 90T

h

Half Life EquationHalf Life Equation

N=NN=N00ee-kt-kt

K=K= ln 2 T1/2

Theory of RelativityTheory of Relativity

∆∆E= (∆m)cE= (∆m)c22

C is the speed of light (2.9*10C is the speed of light (2.9*1088 m/s m/s22)) m is mass (kg)m is mass (kg) E is energy (Joules)E is energy (Joules)