Ch.19 - Nuclear ChemistrySee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

The Valley or Band of Stability represents the area where stable, non-radioactive isotopes exist based on their ratio of neutrons to protons. 

Valley of Stability 

Whenever the difference between neutrons to protons within a nucleus is significant enough an isotope is radioactive. 

Concept #1: The central idea of nuclear chemistry is that unstable nuclei will give off radiation. 

Neutrons act like the glue that keeps the nucleus together. The more neutrons present then the greater the attractive strong force, while the more protons then the greater the repulsive Coulombic force

Concept #2: Non-radioactive isotopes with the optimum number of neutrons to protons will lie within the Valley of Stability, while radioactive isotopes will lie outside of it. 

Example #1: Determine if the following nuclide will undergo alpha decay, beta decay or positron emission.

Hydrogen-3                                                                              

 

Example #2: Determine if the following nuclides will undergo alpha decay, beta decay or positron emission.

Radon-222

Example #3: Determine if the following nuclides will undergo alpha decay, beta decay or positron emission.

Magnesium-50

Additional Problems
Why does the band of stability curve upward at high atomic numbers? A. Excess neutrons are required due to the repulsion between the protons. B. If we have too many protons, not enough electrons will be orbiting the atom to keep it electrically neutral overall. C. Excess protons are required to help keep the neutrons from sticking together as neutrons have no charge. D. Atoms with high atomic numbers have a large number of electrons orbiting the nucleus. This increased number of electrons requires a lot of extra mass in the nucleus to keep the electrons in their orbit.
Which of the following nuclides is likely to lie above the band of stability? (a) 15O (b) 39C (c) 3He (d) 9Li (e) 13N
A radioisotope which is sometimes used by doctors to pinpoint a brain tumor is a. carbon-12 b. lead-206 c. technetium-99 d. uranium-238
Which radioisotope is used to treat thyroid disorders? a. Co-60 b. I-131 c. C-14 d. U-238
A radioactive isotope used in the study of many organic reaction mechanisms is a. carbon-12 b. carbon-14 c. oxygen-16 d. oxygen-18
Which of the following elements is stable? a. Carbon, atomic number 6 b. Boron, atomic number 5 c. Fluorine, atomic number 9 d. Neon, atomic number 10
Which of the following isotopes would you expect to be stable?a. uranium-238b. 4Hec. oxygen-16d. 208Poe. 58Ni
Predict a likely mode of decay for the following unstable nuclide.Sb-132a. beta decay b. alpha decayc. positron emission
Predict a likely mode of decay for the following unstable nuclide.Te-139a. beta decay b. alpha decayc. positron emission
Predict a likely mode of decay for the following unstable nuclide.Ba-123a. beta decay b. alpha decayc. positron emission
Using general trends, predict the stability of the following nuclei. (stable or radioactive)a. Iron-56 b. sulfur-32 c. potassium-44 d. uranium-235 e. cobalt-58
Which of the following isotopes would you expect to be stable?i. carbon-12ii. 4Heiii. uranium-238iv. 58Niv. 208Po
Predict a likely mode of decay for each of the following unstable nuclides. Explain why. a. Mo-109 b. Fr- 202 c. Rn- 196 d. Sb - 132 e. P - 27 f. Ru - 90
Using general trends, predict the stability of the following nuclei as RADIOACTIVE or STABLE.1. arsenic-822. potassium- 443. radium- 2334. calcium- 405. zinc- 64
Which type of nuclear decay is the following radioactive isotope likely to undergo? All known stable isotopes are shown on the graph. The points form what is known as the "belt of stability". If a radioactive isotope is above the belt of stability, think about what type of decay would decrease its N/Z ratio. If an unstable isotope is below the belt of stability, think about what type of decay would increase its N/Z ratio. If a radioactive isotope is off the chart (Z > 83), think about what type of decay would decrease Z the most. a. beta decay b. alpha decay c. positron emission or electron capture
Which type of nuclear decay is the following radioactive isotope likely to undergo?a. alpha decayb. beta decayc. positron emission or electron capture
Which of the following isotopes would you expect to be stable?a. 208Pbb. Carbon-12c. Uranium 235d. 4Hee. 208Po