15.4 Lead (Z = 82, A = 214) decays in a series of steps. The nucleus emits 2 negative betas, 1 alpha, 1 negative beta, 1 alpha,
and 1 negative beta. What is the final daughter product?
i. Lead-206
ii. Lead-205
iii. Lead-222
iv. Lead-210
v. None of these
15.5 Uranium (Z = 92, A = 234) decays in a series of steps. The nucleus emits 4 alphas, 1 negative beta, 2 alphas, 3 negative
betas, and finally, 1 alpha. What is the final daughter product?
i. Lead-206
ii. Lead-208
iii. Lead-210
iv. Lead-212
v. Uranium-206
15.6 Uranium-238 (Z = 92) decays by alpha emission to thorium-234 (Z = 90), by emitting a helium-4 nucleus. Your friend claims
to have witnessed a new type of decay where the uranium-238 emitted a helium-3 nucleus and became a thorium-235 atom.
Prove that this is impossible for an isolated U-238 atom. Here is some helpful data: U-238 has an atomic mass of 238.051 u,
the mass of a helium-3 nucleus is 3.014 u, and the mass of a Th-235 atom is 235.048 u.Section 17 - Radioactive decay and half-lives
17.1 Carbon-14 has a half-life of 5730 years. After four half-lives have elapsed, what percentage of an initially pure sample would
remain unchanged?
percentSection 18 - Interactive problem: radioactive dating
18.1 Using the simulation in the first interactive problem in this section, determine the half-life of Carbon-14.i. 16000
ii. 11460
iii. 5730
iv. 2865years18.2 (a) Use the information for the second interactive problem in this section to determine the number of half-lives that elapsed
between the time the pure lead-209 was dumped and midnight. (b) Use the second simulation to measure the half-life of lead-- (c) Using the information given about when each suspect was spotted, determine who is the guilty party.
(a) half-lives have elapsed
(b) hours
(c) i. Anna
ii. Sara
iii. Katherine
(^720) Copyright 2000-2007 Kinetic Books Co. Chapter 38 Problems