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Table 1. Nuclear Chemistry Versus Traditional Chemistry

Traditional	Nuclear
reactivity depends primarily on valence electrons, nucleus does not participate	in a reaction, electrons are irrelevant, only nucleus is considered
mass is conserved	mass is converted to energy and back E = mc^2
atoms are same on both side	nucleons same on both sides
	energies involved much higher than traditional

Table 2. Properties of Elementary Particles

Class name symbol charge mass other information

(m_e*)

photon gamma γ 0 0

lepton neutrino v 0 0 associated with e or μ

electron e,β^- -1 1

positron β⁺ +1 1

muon μ^+,- ±1 207 μ ® e + v + v

hadron

meson pion π^+,- ±1 273.2 π ® μ + v (anti if -)

pion π⁰ 0 226.2 π®γ + γ

kaon K⁺, K^- ±1 966.1

baryon proton p +1 1836

neutron n 0 1838.6 n- p + e + v

*m_e is the mass of an electron 0.000549 dalton or 9.100 X 10^-28 g

**neutrinos and antineutrinos have some mass, but it is too small to be measured.

Antiparticles are represented with a bar over the symbol. Charged antiparticles have all the same properties as the regular particle, but are opposite charges. A positron is the antiparticle of an electron.

Table 3. Types of Radioactive Emissions

type	symbol	mass (Da)	charge	mass number	Q factor	velocity*	pentration
alpha	a	4.0026	+2	4	20	0.1c	low
beta	β^-, e	0.0055	-1	0	1	0.9c	low to moderate
positron**	β^+	0.0055	+1	0	1	0.9c	low to moderate
gamma	γ	0	0	0	1	c	high
proton	p	1.0073	+1	1	10	0.1c	low to moderate
neutron	n	1.0087	0	1	2-10	0.1c	very high
x-ray	x	0	0	0	1	c	high

* this is the maximum velocity, where c represents the speed of light

** positrons usually only exist for a nanosecond before being annhilated by colliding with an electron and being converted to energy

Table 4. Acute Effects of Radiation³

dose effect

(rem)

25-50 number of white blood cells decreases (temporary)

temporary sterility

200 damage to bone marrow (not complete and reversible)

GI symptons, nausea and vomiting

general malaise and fatigue

loss of hair

some deaths

450 approximate LD₅₀/30 (50% of the population exposed to this dose would die in 30 days of exposure

400-600 complete but reversible loss of bone marrow function

more severe symptoms as at 200 rem

700 irreversible bone marrow damage

survival unlikely

1000 severe diarrhea, nausea and vomiting soon after exposure

death probable in 1-2 weeks

2000 central nervous system damaged

unconsciousness within minutes, death in hours or days

Appendix 1. Units in Nuclear chemistry

Bequerel (Bq) -- one disintegration per second

Curie (Ci) -- 3.7 X 10¹⁰ disintegrations per second

Dose -- quantity of energy that is actually put into a medium by the incoming radiation

Does equivalent (H) --- absorbed dose multiplied by the quality factor. Usual unit is “rem”

Exposure (X) ---total electrical charge (ionization) produced in a given mass (or volume) of air

Gray (Gy) -- dose that will deposit one joule of energy in one kilogram of absorbing material

Linear energy transfer (LET) -- rate at which energy is transferred to a given region of matter. Usual units are keV/μm

Quality factor (Q) -- related to LET to account for differences in types of radiation

Rad (rad) -- dose that will deposit 0.01 J of energy in one kilogram of absorbing material

Rem (rem) -- dose in rads times Q; measurement of dose equivalent

Röntgen (R) -- quantity of x of γ radiation that would produce 1 esu of electrical charge in 0.001293 g of dry air (1 cm³at STP).

Sievert (Sv) -- measurement of dose equivalent; dose in gray times Q

Equivalents

1 R º 2.58 X 10^-4 C/kg for γ rays only, 1 R » 1 rad

1 rad = 10^-2 J/kg rem = rad x Q

1 Gy = 1 J/kg = 100 rad Sv = Gy x Q

For γ rays: Exposure Rate (mR/h) = 6 AEn/d²

A = activity (mCi); E = energy of γ ray; n number of γ rays of energy E emitted per decay; d = distance to source (ft)

For β rays: dose rate (mrad/h) = 338000 A/d²

A = activity (mCi); d = distance (cm)

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