Deck 19: Radioactivity and Nuclear Energy

Question 1

The nucleus is believed to be made of particles called nucleons.

Answer 1

True

Question 2

When a uranium-235 nucleus is struck with a neutron, xenon-144 and strontium-90 nuclei are produced, along with some neutrons. How many neutrons are produced?

A) 2
B) 1
C) 3
D) 4
E) 5

Answer 2

2

Question 3

Choose the particle having a relative mass of 0 amu and a charge of +1.

A) alpha particle
B) beta particle
C) proton
D) neutron
E) none of these

Answer 3

none of these

Question 4

Actinium-229 undergoes beta particle production. What is the other product?

A)
B)
C)
D)
E) none of these

Question 5

After 240 years, 75% of the radioactive nuclides in a particular sample of an isotope have decayed. What is the half-life of this radioactive isotope?

A) 120 years
B) 80 years
C) 480 years
D) 60 years
E) 320 years

Question 6

The iodine-131 nuclide has a half-life of 8.0 days. If you originally have a sample containing 728-g of I-131, after 6.86 weeks you will have

A) 11.4 g
B) 22.75 g
C) 6.3 g
D) 45.5 g
E) less than 1 gram

Question 7

When decays by producing an alpha particle, the product nuclide is ______________.

Question 8

When is bombarded by (and absorbs) a proton, a new nuclide is produced plus an alpha particle. The nuclide produced is ______________.

Question 9

A particular radioactive element has a half-life of 63 days. What percent of the original sample is left after 189 days?

A) 12.50 %
B) 25.00 %
C) 75.00 %
D) 50.00 %
E) 33.33 %

Question 10

A sample of a radioactive element decays to 25% of its original number of radioactive nuclides in 48 years. What is the half-life of this radioactive element?

A) 24 years
B) 12 years
C) 96 years
D) 6 years
E) 48 years

Question 11

A particular radioactive isotope has a half-life of 3.10 weeks. What fraction of the original sample is left after 86.8 days?

A) 1/16
B) 1/4
C) 1/8
D) 1/32
E) none of these

Question 12

The element curium (Z = 242, A = 96) can be produced by positive-ion bombardment when an alpha particle collides with which of the following nuclei? Recall that a neutron is also a product of this bombardment.

A)
B)
C)
D)
E)

Question 13

Complete the table for these radioactive particles:
Name
Charge
Mass Number
Alpha
Beta
Gamma

Question 14

The cesium-137 nuclide has a half-life of 30 years. After 90 years, about 10 g remains. The original mass of the cesium-137 is closest to

A) 80 g
B) 60 g
C) 100 g
D) 90 g
E) 70 g

Question 15

The atomic particle having a mass of 0 amu and a charge of -1 is

A) an electron
B) a neutron
C) an alpha particle
D) a proton
E) none of these

Question 16

Polonium is a radioactive isotope which decays by the loss of an alpha particle. What is the second product of this decay?

A)
B)
C)
D)
E) none of these

Question 17

Alpha particles are

A) electrons
B) protons
C) neutrons
D) helium nuclei
E) X rays

Question 18

Lithium-8 is a beta producer. The product nuclide is ______________.

Question 19

The half-life of a radioactive nuclide is

A) that period of time in which 25% of the original number of atoms undergoes radioactive decay.
B) the time at which the isotope becomes nonradioactive.
C) that period of time in which 50% of the original number of atoms undergoes radioactive decay.
D) the period of time it takes to reduce the radioactivity by 100%.
E) none of the above

Question 20

Atoms that have identical atomic numbers but different mass numbers are called radiotracers.

Question 21

When a curium-242 nucleus is struck with an alpha particle, a neutron is produced along with a new nuclide. What is this new nuclide?

A) californium-245
B) californium-246
C) berkelium-243
D) berkelium-245
E) none of these

Question 22

Five radioactive isotopes have the following half-lives. Which half-life indicates the isotope that would be said to have the greatest activity of this group?

A) 11.4 hours
B) 4.4 days
C) 41 hours
D) 2.9 years
E) 49 days

Question 23

Nuclear fusion uses heavy nuclides such as as fuel.

Question 24

Strontium-90 from radioactive fallout is a health threat because, like ______________, it is incorporated into bone.

A) iodine
B) cesium
C) iron
D) calcium
E) uranium

Question 25

A breeder reactor is one that produces from .

Question 26

Some radioactive isotopes decay by emitting a positron. Which new nuclide is formed when undergoes radioactive decay by positron production?

A)
B)
C)
D)
E)