Nuclear Chemistry

Parts of the atom ParticleCharge Mass (g) Mass (amu) Proton x Neutron x Electron 9.110x /1839

Parts of the atom

Nuclear chemistry Most chemical changes deals with the electron Most chemical changes deals with the electron Nuclear chemistry deals with changes in the nucleus, often accompanied by a release of a large amount of energy Nuclear chemistry deals with changes in the nucleus, often accompanied by a release of a large amount of energy

Radiation Radiation is energy in transit in the form of high speed particles and electromagnetic waves Radiation is energy in transit in the form of high speed particles and electromagnetic waves Radiation cannot be tasted, felt, or smelt, but has the potential to do a great deal of damage Radiation cannot be tasted, felt, or smelt, but has the potential to do a great deal of damage There are 4 particles or waves of radiation we will learn about There are 4 particles or waves of radiation we will learn about Alpha Alpha Beta Beta Gamma Gamma Neutron Neutron

Alpha particle Symbol: 2 4 He or  Symbol: 2 4 He or  It is composed of 2 protons, 2 neutrons, has a mass of 4 amus and a charge of 2 + It is composed of 2 protons, 2 neutrons, has a mass of 4 amus and a charge of 2 + Low energy Low energy

Beta particle Symbol: -1 0 e or  Symbol: -1 0 e or  A high energy electron A high energy electron Charge -1 Charge -1

Gamma rays Gamma rays unlike the  or  particle is not a particle, instead a ray similar to an x-ray Gamma rays unlike the  or  particle is not a particle, instead a ray similar to an x-ray Symbol:  Symbol:  It is a ray it has no mass or charge It is a ray it has no mass or charge Very high energy Very high energy

Neutron Symbol: 0 1 n Symbol: 0 1 n It has a mass of one, no protons, and no charge It has a mass of one, no protons, and no charge

Types of nuclear radiation Radiation Type of RadiationMass(AMU)Charge Shielding material Alpha Particle42 Paper, skin, clothes Beta Particle1/1836±1 Plastic, glass, light metals Gamma Electromag -netic Wave 00 Dense metal, concrete, Earth Neutrons Particle10 Water, concrete

From:

Review: Atomic number and mass number Atomic number = number of protons = symbol. Atomic number = number of protons = symbol. Atoms are electronically neutral. Atoms are electronically neutral. Number of electrons = number of protons Number of electrons = number of protons Mass number = # protons + # neutrons Mass number = # protons + # neutrons ElementProtonsElectronNeutrons H O S Cl Rn

A +/-q Z X X=symbol Z=atomic number (# of protons) A=mass number (# of protons + # neutrons) q= charge (+=electrons<protons, -=electrons>protons) Atomic number and mass number How would we write H in this form?

Isotopes Isotopes Isotopes

Isotopes Isotopes-atoms of the same element (same number of protons) that have different number of neutrons Isotopes-atoms of the same element (same number of protons) that have different number of neutrons Mg Mg Mg

Radioactive decay (natural) Radioactive decay-when a nucleus breaks down by emitting radiation (naturally occurring) Radioactive decay-when a nucleus breaks down by emitting radiation (naturally occurring) U → Th + Which of the radioactive particles? Radioactive nucleus New nucleus radiation ( , , or  ) → +

Radioactive decay-when a nucleus breaks down by emitting radiation (naturally occurring) Radioactive decay-when a nucleus breaks down by emitting radiation (naturally occurring) Radioactive nucleus New nucleus radiation ( , , or  ) → U → Th He Radioactive decay (natural)

Radioactive decay  and  : practice Am → ? He Am → ? He ? → 7 14 N e ? → 7 14 N e ? → S e ? → S e Co → Ni +? Co → Ni +? Ra → Rn + ? Ra → Rn + ? ? → Po He ? → Po He Fe → Co + ? Fe → Co + ?

Radioactive decay  and  : practice Am → Np He Am → Np He 6 14 C → 7 14 N e 6 14 C → 7 14 N e P → S e P → S e Co → Ni e Co → Ni e Ra → Rn He Ra → Rn He Rn → Po He Rn → Po He Fe → Co e Fe → Co e

Gamma decay There are very few pure gamma emitters, although gamma radiation accompanies most  and  decay There are very few pure gamma emitters, although gamma radiation accompanies most  and  decay In radiology one of the most commonly used gamma emitters is Tc In radiology one of the most commonly used gamma emitters is Tc 43 99m Tc → Tc +  43 99m Tc → Tc +  A gamma decay will have no change in the atomic number or atomic mass A gamma decay will have no change in the atomic number or atomic mass

Bombardment Reaction Bombardment reaction-bombarding 2 stable atoms together, creating a radioisotope Bombardment reaction-bombarding 2 stable atoms together, creating a radioisotope All of the known elements whose atomic number is greater than 92 were created from bombardment reactions All of the known elements whose atomic number is greater than 92 were created from bombardment reactions

Bombardment reactions: practice Cf + ? → Db n Cf + ? → Db n Ni H → ? He Ni H → ? He Co + ? → Mn He Co + ? → Mn He 7 14 N He → 8 17 O + ? 7 14 N He → 8 17 O + ?

Bombardment reactions: practice Cf N → Db n Cf N → Db n Ni H → Co He Ni H → Co He Co n → Mn He Co n → Mn He 7 14 N He → 8 17 O H 7 14 N He → 8 17 O H