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Problem 15b
Decay of which nucleus will lead to the following products: (b) chromium-50 by positron emission?
Problem 15c
Decay of which nucleus will lead to the following products: (c) tantalum-179 by electron capture?
- What particle is produced during the following decay processes: (a) sodium-24 decays to magnesium-24, (b) mercury-188 decays to gold-188, (d) plutonium-242 decays to uranium-238?
Problem 16
Problem 16c
What particle is produced during the following decay processes: (c) iodine-122 decays to xenon-122?
- The naturally occurring radioactive decay series that begins with 235 92U stops with the formation of the stable 207 82Pb nucleus. The decays proceed through a series of alpha-particle and beta-particle emissions. How many of each type of emission are involved in this series?
Problem 17
- A radioactive decay series that begins with 23290Th ends with the formation of the stable nuclide 20882Pb. How many alpha-particle emissions and how many beta-particle emissions are involved in the sequence of radioactive decays?
Problem 18
Problem 19a
Predict the type of radioactive decay process for the following radionuclides: (a) 85B.
Problem 19b
Predict the type of radioactive decay process for the following radionuclides: (b) 6829Cu.
Problem 19c,d
Predict the type of radioactive decay process for the following radionuclides: (c) phosphorus-32. (d) chlorine-39.
Problem 20a
Each of the following nuclei undergoes either beta decay or positron emission. Predict the type of emission for each: (a) tritium, 31H.
Problem 20b
Each of the following nuclei undergoes either beta decay or positron emission. Predict the type of emission for each: (b) 8938Sr.
- One of the nuclides in each of the following pairs is radioactive. Predict which is radioactive and which is stable: (a) 39₁₉K and 40₁₉K. (b) ²⁰⁹Bi and ²⁰⁸Bi. (c) nickel-58 and nickel-65.
Problem 21
- One nuclide in each of these pairs is radioactive. Predict which is radioactive and which is stable: (a) 4020Ca and 4520Ca. Explain your choice in each case. (b) 12C and 14C. Explain your choice in each case. (c) lead-206 and thorium-230. Explain your choice in each case.
Problem 22
- Which of the following nuclides have magic numbers of both protons and neutrons: (a) helium-4, (b) oxygen-18, (c) calcium-40, (d) zinc-66, (e) lead-208?
Problem 23
Problem 24
Despite the similarities in the chemical reactivity of elements in the lanthanide series, their abundances in Earth's crust vary by two orders of magnitude. This graph shows the relative abundance as a function of atomic number. Which of the following statements best explains the sawtooth variation across the series? (a) The elements with an odd atomic number lie above the belt of stability. (b) The elements with an odd atomic number lie below the belt of stability. (c) The elements with an even atomic number have a magic number of protons. (d) Pairs of protons have a special stability.
- Which of the following statements best explains why alpha emission is relatively common, but proton emission is extremely rare? (a) Alpha particles are very stable because of magic numbers of protons and neutrons. (b) Alpha particles occur in the nucleus. (c) Alpha particles are the nuclei of an inert gas. (d) An alpha particle has a higher charge than a proton.
Problem 25
Problem 26
Which of the following nuclides would you expect to be radioactive: 5826Fe, 6027Co, 9241Nb, mercury-202, radium-226? Justify your choices.
- Which statement best explains why nuclear transmutations involving neutrons are generally easier to accomplish than those involving protons or alpha particles? (a) Neutrons are not a magic number particle. (b) Neutrons do not have an electrical charge. (c) Neutrons are smaller than protons or alpha particles. (d) Neutrons are attracted to the nucleus even at long distances, whereas protons and alpha particles are repelled.
Problem 27
- In 1930, the American physicist Ernest Lawrence designed the first cyclotron in Berkeley, California. In 1937, Lawrence bombarded a molybdenum target with deuterium ions, producing for the first time an element not found in nature. What was this element? Starting with molybdenum-96 as your reactant, write a nuclear equation to represent this process.
Problem 28
- Complete and balance the following nuclear equations by supplying the missing particle: (a) 25298Cf + 105B → 310n + ? (c) 11H + 115B → ?
Problem 29
Problem 29b
Complete and balance the following nuclear equations by supplying the missing particle: (b) 21H + 32He → 42He + ?
Problem 29d
Complete and balance the following nuclear equations by supplying the missing particle: (d) 12253I → 12254Xe + ?
Problem 29e
Complete and balance the following nuclear equations by supplying the missing particle: (e) 5926Fe → 0-1e + ?
Problem 30a
Complete and balance the following nuclear equations by supplying the missing particle: (a) 147N + 42He¡? + 11H
Problem 30d
Complete and balance the following nuclear equations by supplying the missing particle: (d) 5826Fe + 2 10n¡6027Co + ?
Problem 30e
Complete and balance the following nuclear equations by supplying the missing particle: (e) 23592U + 10n¡13554Xe + 2 10n + ?
- Write balanced equations for (a) 238922U + 1n -> 224194Pu. (b) 147N + 1a -> 1p + 178O. (c) 5626Fe + 1a -> 1b + 6029Cu.
Problem 31
- Write balanced equations for each of the following nuclear reactions: (a) 23892U + 10n → g + 23992U. (b) 168O + 11p → a + 179N. (c) 188O + 10n → b- + 199F.
Problem 32
- Each statement that follows refers to a comparison between two radioisotopes, A and X. Indicate whether each of the following statements is true or false. (a) If the half-life for A is shorter than the half-life for X, A has a larger decay rate constant.
Problem 33
- It has been suggested that strontium-90 (generated by nuclear testing) deposited in the hot desert will undergo radioactive decay more rapidly because it will be exposed to much higher average temperatures. (a) Is this a reasonable suggestion? (Section 14.5) (b) Does the process of radioactive decay have an activation energy, like the Arrhenius behavior of many chemical reactions (Section 14.5)?
Problem 34