Multiple Choice
The radioisotope potassium-40 decays to argon-40 by positron emission with a half-life of 1.3 * 109 yr. A sample of moon rock was found to contain 78 argon-40 atoms for every 22 potassium-40 atoms. The age of the rock is
A) 8.1 * 10-10 yr.
B) 2.4 * 109 yr.
C) 2.8 * 109 yr.
D) 4.6 * 109 yr.
E) 6.8 * 109 yr.
Correct Answer:
Verified
Correct Answer:
Verified
Q50: Consider the following decay series: <img
Q51: The type of nuclear process illustrated
Q52: What nuclear fuel is produced in a
Q53: A sample of a radioisotope shows an
Q54: Tritium is a radioisotope of hydrogen having
Q56: When a <sup>162</sup>Re nucleus emits an alpha
Q57: Rubidium-87 decays by beta decay with a
Q58: Strontium-90 has a half-life of 28.8 years.
Q59: Find the nuclear binding energy of uranium-234
Q60: A balanced nuclear equation representing the