Question 1

_____ are the subatomic particles that have the smallest mass.

Accepted Answer

A)  Protons 
B)  Neutrons 
C)  Electrons 
D)  Protons and neutrons 
E)  Protons, neutrons, and electrons

Question 2

Radioactive decay is the process by which

Accepted Answer

A)  radioisotopes become more stable. 
B)  radioisotopes emit radiation. 
C)  radioisotopes emit high-energy particles and/or electromagnetic radiation. 
D)  an element of one type can change to an element of another type. 
E)  All of the above

Question 3

Which of the following statements describes how our model of the atom has changed?

Accepted Answer

A)  The model of the atom has never changed. 
B)  Electrons are now commonly directly observed. 
C)  Electrons are now known to orbit the nucleus like a planet orbits the Sun. 
D)  The path of a single electron can now be followed exactly. 
E)  We now determine the probabality of finding an electron in a region of space.

Question 4

Most of the micronutrients are

Accepted Answer

A)  transition metals. 
B)  metalloids. 
C)  nonmetals. 
D)  alkali earth metals. 
E)  noble gases.

Question 5

The radioisotope undergoing decay is often called the

Accepted Answer

A)  reactant. 
B)  product. 
C)  parent nuclide. 
D)  decayer. 
E)  daughter nuclide.

Question 6

Which of the following describes a benefit of using rems to measure the quantity of radiation that a patient has received instead of curies?

Accepted Answer

A)  Rems measure the biological effect of radiation, not just quantity. 
B)  Curies measure the biological effect of radiation, not just quantity. 
C)  Rems measure the amount of energy absorbed, not just quantity. 
D)  Curies measure the amount of energy absorbed, not just quantity. 
E)  There is no benefit.

Question 7

An element is a solid at room temperature and a shiny, metallic grey. However, it is a poor conductor of electricity and temperature and it is also brittle. Which of the following elements fits this description?

Accepted Answer

A)  oxygen 
B)  lithium 
C)  helium 
D)  antimony 
E)  iron

Question 8

According to the graph, radioactive decay is a(n) _________ in radioactivity as a function of time.

Accepted Answer

A)  linear decrease 
B)  linear increase 
C)  exponential decrease 
D)  exponential increase 
E)  random decrease

Question 9

According to the current model of the atom, the part of the diagram labeled B is made up of

Accepted Answer

A)  protons. 
B)  neutrons. 
C)  electrons. 
D)  protons and neutrons. 
E)  protons, neutrons, and electrons.

Question 10

Which of the following is NOT true for the atoms 12C, 13C, and 14C?

Accepted Answer

A)  They all have six electrons. 
B)  They all have the same mass number. 
C)  They all have the same atomic number. 
D)  They are isotopes. 
E)  They all have six protons.

Question 11

The energy diagram below is for an ion of magnesium. To make this ion, the atom that it came from had to_________.

Accepted Answer

A)  become a different atom. 
B)  gain electrons. 
C)  become a nonmetal. 
D)  lose electrons. 
E)  become a metal.

Question 12

According to the periodic table, the atomic mass of potassium (K) is ______. ?

Accepted Answer

A)  4 
B)  19 
C)  39.10 
D)  K 
E)  2

Question 13

Which of the following is the best definition of the term "ionizing radiation"?

Accepted Answer

A)  This is radiation that has enough energy to dislodge a valence electron from an atom. 
B)  This is the radiation that is released during a nuclear reaction. 
C)  This is any electromagnetic radiation. 
D)  This is any nuclear or electromagnetic radiation. 
E)  This is any long-wavelength electromagnetic radiation.

Question 14

In which of the following reactions is the missing particle an alpha particle?

Accepted Answer

A)  
B)  
C)  
D)  
E) All of above

Question 15

Which electron shell is closest to the nucleus of the atom?

Accepted Answer

A)  n =1 
B)  n =2 
C)  n =3 
D)  n =4 
E)  All electrons are equally close to the nucleus.

Question 16

Which isotope in Zirconium is the least abundant?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 17

Phosphorous-32 is a beta emitter with a half-life of 14.3 days. So, after 42 days, a 100-mg sample will have decayed to 25 mg. Which statement best describes where the rest of the 32P went?

Accepted Answer

A)  It disappeared. 
B)  It reacted with air. 
C)  It turned into sulfur and a beta particle. 
D)  It turned into silicon and a beta particle. 
E)  It decomposed into beta particles.

Question 18

Radioisotopes used in medicine typically have short half-lives. Which of the following statements best describes the reason for this?

Accepted Answer

A)  It minimizes the harmful side effects of the radiation. 
B)  They are the isotopes that are the easiest to make. 
C)  These radioisotopes occur naturally. 
D)  Only small amounts of them are required. 
E)  These radioisotopes emit the correct type of radioactive particle.

Question 19

Electron shells closest to the nucleus are occupied before electron shells farther from the nucleus because the electrons shells closest to the nucleus are

Accepted Answer

A)  pulled toward the nucleus by gravity. 
B)  protected by the outer shell. 
C)  attracted to the nucleus for reasons unknown. 
D)  more stable than electrons farther from the nucleus. 
E)  Actually, electrons farther from the nucleus are filled first.

Question 20

What type of radiation is emitted when U-235 undergoes radioactive decay?

Accepted Answer

A)  alpha particle 
B)  beta particle 
C)  positron 
D)  gamma ray 
E)  x-ray

Exam 2: Atomic Structure and Nuclear Radiation