Question 1

The time needed for a radioactive sample to decay to one-half of its original activity is called the ________.

Accepted Answer

The answer of The time needed for a radioactive sample...

Question 2

When an alpha particle is emitted from the nucleus of an atom, the nuclear mass

Accepted Answer

A) increases by two units. 
B) decreases by four units. 
C) increases by one unit. 
D) decreases by two units. 
E) remains the same.

Question 3

A patient receives 10 mrads of gamma radiation. If the factor that adjusts for biological damage for for gamma radiation is 1, how many mrems did the patient receive?

Accepted Answer

A) 2 mrem 
B) 5 mrem 
C) 10 mrem 
D) 20 mrem 
E) 200 mrem

Question 4

Nuclear fission as used in nuclear power plants produces radioactive waste with long half-lives.

Accepted Answer

A) True 
 B)False

Question 5

When aluminum-27 is bombarded with a neutron, a gamma ray is emitted. What radioactive isotope is produced?

Accepted Answer

A) silicon-27 
B) silicon-28 
C) aluminum-28 
D) magnesium-27 
E) magnesium-28

Question 6

A person begins to suffer radiation sickness at an exposure level of

Accepted Answer

A) 25 rem. 
B) 5 rem. 
C) 500 rem. 
D) 100 rem. 
E) 600 rem.

Question 7

One symptom of mild radiation sickness is

Accepted Answer

A) a lowered white cell count. 
B) a raised white cell count. 
C) a lowered red blood cell count. 
D) a raised red blood cell count. 
E) a white cell count of zero.

Question 8

Krypton-79 has a half-life of 35 hours. How many half-lives have passed after 105 hours?

Accepted Answer

A) 1 half-life 
B) 2 half-lives 
C) 3 half-lives 
D) 4 half-lives 
E) 5 half-lives

Question 9

In the Sun, nuclei of hydrogen combine to form a larger nucleus and release a great amount of energy. The process is known as

Accepted Answer

A) fission. 
B) fusion. 
C) metathesis. 
D) chain reaction. 
E) ionization.

Question 10

The diagnostic imaging technique that depends on magnetic fields and radio waves, not radioactivity, is called ________.

Accepted Answer

The answer of The diagnostic imaging technique that depends on...

Question 11

A nuclear equation is balanced when

Accepted Answer

A) the same elements are found on both sides of the equation. 
B) the sum of the mass numbers and the sum of the atomic numbers of the particles and atoms are the same on both sides of the equation. 
C) the same particles and atoms are on both sides of the equation. 
D) different particles and atoms are on both sides of the equation. 
E) the charges of the particles and atoms are the same on both sides of the equation.

Question 12

F there are

Accepted Answer

A) 85 protons and 38 neutrons. 
B) 47 protons and 38 neutrons. 
C) 38 protons and 47 neutrons. 
D) 38 protons and 85 neutrons. 
E) 85 protons and 47 neutrons.

Question 13

Why is it important that radioisotopes used in diagnostic tests have short half-lives?

Accepted Answer

A) These radioisotopes have a greater activity so they are easier to monitor. 
B) This minimizes the harmful side effects of the radiation. 
C) This is necessary so the radioisotopes will have high energy. 
D) These radioisotopes are less expensive. 
E) These radioisotopes are more abundant in nature.

Question 14

The nuclear reaction shown below is an example of what type of process? 
Th →  Rn +  He

Accepted Answer

A) fusion 
B) fission 
C) translation 
D) alpha decay 
E) betadecay

Question 15

What is missing in the nuclear reaction shown below? 
 Zn +  p → ________

Accepted Answer

A) a proton 
B) Ga 
C) Ga 
D) Zn 
E) Cu

Question 16

The half-life of bromine-74 is 25 min. How much of a 4.0 mg sample is still active after 75 min?

Accepted Answer

A) 0.50 mg 
B) 1.0 mg 
C) 2.0 mg 
D) 0.25 mg 
E) 4.0 mg

Question 17

The correct symbol for hydrogen-3 is  He.

Accepted Answer

A) True 
 B)False

Question 18

What is the radioactive particle released in the following nuclear equation? 
 Sr →  Y + ?

Accepted Answer

A) alpha particle 
B) beta particle 
C) gamma ray 
D) proton 
E) neutron

Question 19

When a positron is emitted from the nucleus of an atom, the nuclear mass

Accepted Answer

A) increases by two units. 
B) decreases by one unit. 
C) increases by one unit. 
D) decreases by two units. 
E) remains the same.

Exam 5: Nuclear Chemistry