Chemistry Regents Review: Nuclear Chemistry & Unit 2 (week #5)

Why aren’t radioactive isotopes included in the calculation of the weighted average?

because they aren’t stable in a natural environment & random breakages of particles being emitted

Transmutation

when an element turns into another

Nucleons

particles in the nucleus

• if the ratio of nucleons changes → chemical changes

Half-Life

time required for half of the amount of an isotope to decay

Half-Life Chart

When you heat a radioactive material its half-life…

remains the same

Nuclear Fusion (fuse)

2 smaller and nuclei fuse tgth and form one bigger and heavier nucleus

• H & He ONLY

• very high temps ONLY

Nuclear Fission

a larger nucleus splits into 2 or ore smaller nuclei

2 ways nuclear fission can occur

• spontaneous (by itself)

• artificially (absorbing a neutron)

Nuclear Fission and Fusion both take mass and….

convert it to make very large amounts of energy

Radioactivity

radioactive isotopes spontaneously decay over time

As penentration power increases…

ionization decreases

Short Half Lives

• good for diagnosing disorders

Similarity of Ionization Energy and Bright Line Spectra

• both emit energy

Differences of Ionization Energy and Bright Line Spectra

• ionization loses an e-

• ionization requires more energy (physically removing an e- from an element while BLS is just moving e- up and down the energy shells)

Relative Abundance

Carbon-14 is used for

dating of once living remains

Cobalt-60 is used for

treatment of cancer

Iodine-131 is used for

treatment and diagnosis of thyroid disorders

Uranium-239 is used for

dating of geological reamins