3: Nuclear Chemistry and Medicine

Sacramento City College
CHEM 309: General, Organic and Biochemistry
Prof. Dianne Bennett

Agenda (Fall)  •   Agenda (Spring)  •  Homework Problems

1. Chapter 2: The Classical Wave Equation
2. 2.1: The One-Dimensional Wave Equation
3. 2.2: The Method of Separation of Variables
4. 2.3: Oscillatory Solutions to Differential Equations
5. 2.4: The General Solution is a Superposition of Normal Modes
6. 2.5: A Vibrating Membrane
7. 2.E: The Classical Wave Equation (Exercises)

 •  Homework Solutions

1. Chapter 11: Computational Quantum Chemistry
2. 11.1: Gaussian Basis Sets
3. 11.2: Extended Basis Sets
4. 11.3: Orbital Polarization Terms in Basis Sets
5. 11.4: The Ground-State Energy of H2H2
6. 11.5: Quantum Calculations
7. 11.E: Computational Quantum Chemistry (Exercises)

Chapters

1. Chapter 12: Group Theory: The Exploitation of Symmetry
2. 12.1: The Exploitation of Symmetry
3. 12.2: Symmetry Elements
4. 12.3: Symmetry Operations Define Groups
5. 12.4: Symmetry Operations as Matrices
6. 12.5: The C3VC3V Point Group
7. 12.6: Character Tables
8. 12.7: Characters of Irreducible Representations
9. 12.8: Using Symmetry to Solve Secular Determinants
10. 12.9: Generating Operators
11. 12.E: Group Theory: The Exploitation of Symmetry (Exercises)

  •  Video Tutorials

1. Chapter 13: Molecular Spectroscopy
2. 13.1: The Electromagnetic Spectrum
3. 13.2: Rotations Accompany Vibrational Transitions
4. 13.3: Unequal Spacings in Vibration-Rotation Spectra
5. 13.4: Unequal Spacings in Pure Rotational Spectra
6. 13.5: Vibrational Overtones
7. 13.6: Electronic Spectra Contain Electronic, Vibrational, and Rotational Information
8. 13.7: The Franck-Condon Principle
9. 13.8: Rotational Spectra of Polyatomic Molecules
10. 13.9: Normal Modes in Polyatomic Molecules
11. 13.10: Irreducible Representation of Point Groups
12. 13.11: Time-Dependent Perturbation Theory
13. 13.12: The Selection Rule for the Rigid Rotator
14. 13.13: The Harmonic Oscillator Selection Rule
15. 13.14: Group Theory Determines Infrared Activity
16. 13.E: Molecular Spectroscopy (Exercises)

 •  Basic Knowledge Practice Quizzes

There are select answers to these problems here.

Radioisotopes

(01) What component of the atom, which has previously been left out of the types of reactions studied so far, enables nuclear reactions to occur? What is the primary difference between standard reactions and ones involving nuclear chemistry? Think of subatomic particles and which are involved in each type of reaction.

(02) Isotopes have been briefly touched upon before. Between isotopes of the same element, what is the distinguishing characteristic that shows how they differ from one another? What features remain identical between isotopes of the same element?

(03) Demonstrate your understanding of isotopes by filling in the blank portions of the table below.

Isotope Name	Atomic Number	Mass Number	Number of Neutrons	Number of Protons
Carbon-14				6
	84	211
Potassium-40		40
	94		150
Iodine-130				53
		66	36

Electromagnetic Radiation

(04) Why is it that on a daily basis, the background radiation, in the form of the many waves and wavelengths all around us, we need no special protection, while when we need to get a broken limb X-rayed, we have to wear things like lead vests? What characteristic makes X-rays and other similar types of radiation so much more hazardous?

(05) Take each of the following examples of electromagnetic radiation and rank them from lowest energy to highest energy: Infrared, gamma rays, ultraviolet, radio, X-rays, visible light, microwaves.

(06) Each of the following pairs of electromagnetic radiation are at different levels in terms of their respective energies. Circle the higher-energy radiation.

1. microwaves and radio
2. ultraviolet and X-rays
3. visible light and infrared

(07) For the ultraviolet and infrared regions of the electromagnetic spectrum, explain which region can be potentially harmful biologically and why.

(08) Circle the different forms of electromagnetic radiation from the list below.

1. Gamma rays
2. Protons
3. Alpha particles
4. Microwaves
5. Positrons
6. X-Rays
7. Electrons
8. Beta particles
9. Neutrons

Types of Radioactive Decay

(09) Thorium-232 is a member of the actinide series and, like every element above atomic number 83, has no stable isotopes. Write both an alpha decay reaction and a beta decay reaction for Thorium-232.

(10) Gamma reactions are different from alpha and beta decay reactions. Write out the gamma decay reaction for Uranium-240 and answer the following.

1. What is the daughter nuclide produced from this decay reaction?
2. What, if any, types of electromagnetic radiation are produced by the reaction?
3. Are gamma reactions more hazardous than alpha and beta? Explain.

(11) What is the difference between alpha decay and beta decay? What is the difference between beta decay and positron decay? What is the difference between beta decay and gamma decay?

(12) For each isotope, according to the listed type of decay, name the daughter nuclide produced.

1. Carbon-14 under alpha decay
2. Phosphorus-32 under alpha decay
3. Fluoride-18 under beta decay
4. Iron-56 under beta decay
5. Iridium-193 under alpha decay

(13) Write out the reactions for each of the following.

1. alpha decay of Ge-73
2. positron emission of Yttrium-89
3. formation of Calcium-40 through beta decay
4. Gamma emission of Ba-137

Half-Life

(14) Assume that, at zero half-lives, a sample of an isotope with a mass of 16 grams. The half-life is 5 minutes. After 20 minutes, how many grams remain? How many half-lives have elapsed? What percentage of the material is left? Hint: Using a table can help keep track of half-lives and amounts.

(15) The half-life for Tc-99m is 6 hours. A 100-gram sample of technetium-99 is stored for 30 hours. How much of the radioisotope is left after that time period? How many half-lives have elapsed after the 30 hours?

(16) The half-life for Kr-79 is 34.5 hours. How long would it take for 50 grams of Krypton-79 to decay to 6.25 grams? What percentage of the initial 50 grams does the 6.25 grams represent? How many half-lives did it take to decay down to 6.25 grams?

(17) When being used medically, do radioisotopes with longer or shorter half-lives work better? Explain your reasoning.

(18) If 64 grams of fluorine-18 is administered to a patient, how much will be left after 4 half-lives? If the doctor expects the patient to have less than 5% of it left in their system, how many half-lives will that take?

(19) Decay does not occur all at once when the half-life point is reached; decay is constantly occurring. Knowing this, how long would it take for iron-59 to decay to 25% of its initial amount of radioisotope?

Artificial Radioisotopes

(20) Write the reaction for bombardment of Einsteinium-252 with 3 neutrons to form Nobelium-255 and 3 beta particles.

(21) Some bombardment reactions do not produce different compounds, but can produce isotopes of the same element with a different mass. Write the reaction, and identify the correct isotope of carbon which, when bombarded with two neutrons, will produce the isotope carbon-14.

Energy and Penetrating Power of Nuclear Radiation

(22) If an ion contains 16 protons and 18 electrons, the symbol is S^2-. Write the symbol for an ion containing 12 protons and 10 neutrons.

(23) In situations where getting an X-ray is necessary such as during dental examinations or when seeing if bones are broken, wearing lead aprons and other such protective equipment is essential. Explain how lead provides protection.

(24) Rank the following from least energetic to most energetic: X-rays, beta particles, gamma particles, alpha particles. Then, rank them from least penetrating power to most penetrating power. How do these two rankings compare to one another?

(25) Do any forms of radiation have the same level of energy AND the same penetrating power? Find and name two that share these if possible.

Measurement of Radiation

(26) The following hypothetical situations describe exposure situations to radiation. Describe them as either chronic or acute exposure.

1. An airline pilot frequently in the air most of the week (radiation levels are higher during flight than on the ground).
2. A student who forgets one day to take proper precautions while working on a lab experiments.
3. A dental assistant who handles the X-rays on patients.
4. Someone living in the vicinity of a nuclear plant.
5. A patient given a temporary dose of an isotope for a thyroid problem.