Structure of Matter Ch 1

Question 1

Match the charge with the particle:
A. Electron a. +1
B. Positron b. -1
C. Proton c. 0 (neutral)
D. Neutron
E. Photon

Answer 1

A. Electron b. -1
B. Positron a. +1
C. Proton a. +1
D. Neutron c. 0 (neutral)
E. Photon c. 0 (neutral)

Question 2

Isobars are nuclides that have the same:
A. Number of protons
B. Atomic number
C. Mass number
D. Number of neutrons

Answer 2

C. Mass number

Question 3

Which of the following nuclear transitions produces only photon radiation:
A. Isomeric
B. Electron capture
C. Isobaric
D. Isotopic

Answer 3

A. Isomeric

Question 4

Which of these transitions produces electrons:
A. Isobaric
B. Auger
C. Internal conversion
D. All of the above

Answer 4

D. All of the above

Question 5

What determines the binding energy of an electron:
A. The physical density of the material
B. The shell (K, L, etc.) location of the electrons and the atomic number of the
element
C. The thickness of the material
D. The speed of the electron in the orbit

Answer 5

B. The shell (K, L, etc.) location of the electrons and the atomic number of the
element

Question 6

Match the following symbols with their corresponding parameters:
A. Na a. Plank’s constant
B. A b. Mass number
C. Z c. Atomic number
D. h d. Avogadro’s number

Answer 6

A. Na d. Avogadro’s number
B. A b. Mass number
C. Z c. Atomic number
D. h a. Plank’s constant

Question 7

The mass of an electron at rest is:
A. 1.02 MeV
B. 0.511 MeV
C. 9.81 MeV
D. 5.11 MeV

Answer 7

B. 0.511 MeV

Question 8

One atomic mass unit is the same as:
A. 1.66 x 10-27 Kg
B. 1/12 the mass of a 12C6 nucleus
C. 931 MeV
D. All of the above

Answer 8

D. All of the above

Question 9

The number of atoms in one gram is equal to:
A. The atomic weight divided by the atomic mass
B. Avogadro’s number divided by atomic weight of the atom
C. Avogadro’s number divided by the density of the material
D. The atomic weight divided by Avogadro’s number

Answer 9

B. Avogadro’s number divided by atomic weight of the atom

Question 10

The binding energy of the nucleus is the:
A. Force of repulsion between the electrons of the atoms
B. Force of attraction between the protons and electrons of the atom
C. Energy needed to keep the nuclear particles together
D. Force of attraction between atoms

Answer 10

C. Energy needed to keep the nuclear particles together

Question 11

The mass of an electron is:
A. The same as that of a proton
B. Half of the proton’s mass
C. The same as that of a neutron
D. Much smaller than the mass of a neutron

Answer 11

D. Much smaller than the mass of a neutron

Question 12

Which of the following does not ionize directly:
A. Positron
B. Neutron
C. Alpha particle
D. Electron
E. Proton

Answer 12

B. Neutron

Question 13

Approximately how heavy is a neutron compared to an electron:
A. 10 :1
B. 100 :1
C. 1000 :1
D. 2000 :1

Answer 13

D. 2000 :1

Question 14

The atomic mass number (A) is equal to the:
A. Number of neutrons
B. Number of electrons and protons
C. Number of neutrons, electrons, and protons
D. Mass of electrons minus their binding energies
E. Number of nucleons (protons and neutrons)

Answer 14

E. Number of nucleons (protons and neutrons)

Question 15

The energy equivalent of an atomic mass unit is approximately:
A. 1 keV
B. 10 keV
C. 100 MeV
D. 1000 MeV

Answer 15

D. 1000 MeV

Question 16

The binding energy of an electron is:
A. Highest for the most external shell
B. Highest for the inner most shell
C. Highest for a free electron
D. Highest for the fastest moving electron

Answer 16

B. Highest for the inner most shell

Question 17

A deuteron (2H) is the nucleus of an isotope of hydrogen. Which of the following is
true:
A. It has a mass number of 2
B. It has an atomic number of 2
C. It has a positive charge of 2
D. It has an energy of 2 MeV

Answer 17

A. It has a mass number of 2

Question 18

In order for a photon to ionize an atom, its energy must be:
A. Greater than the binding energy of an electron in the atom
B. Less than the binding energy of an electron in the atom
C. Equal to the binding energy of an electron in the atom
D. None of the above

Answer 18

A. Greater than the binding energy of an electron in the atom

Question 19

An atom is neutral if the number of its electons is equal to its:
A. Number of protons
B. Number of nucleons
C. Atomic weight
D. None of the above

Answer 19

A. Number of protons