Chapter 4:
The Structure of the Atom
Practice Test
1.
What is the charge of a gamma ray?
a.
0
b.
2+
c.
1–
d.
1+
Hint
2.
How is the atomic mass unit (amu) defined?
a.
1/12 the mass of a carbon-12 atom
b.
1/14 the mass of a nitrogen-14 atom
c.
1/16 the mass of an oxygen-16 atom
d.
1/13 the mass of a carbon-13 atom
Hint
3.
The sum of the protons and neutrons in a nucleus is __________?
a.
the atomic number
b.
Avogadro’s number
c.
the mass number
d.
the element number
Hint
4.
Which scientist determined that almost all of an atom’s mass of is located in its nucleus?
a.
Dalton
b.
Thomson
c.
Rutherford
d.
Democritus
Hint
5.
What is the charge of an alpha particle?
a.
2+
b.
0
c.
1–
d.
1+
Hint
6.
What is the negatively—charged particle in an atom?
a.
electron
b.
neutron
c.
proton
d.
positron
Hint
7.
What is the name for the emission of rays and particles by a radioactive material?
a.
radiation
b.
decay
c.
radioactive series
d.
nuclear reactivity
Hint
8.
What is the name of the element that has an atomic number of 3?
a.
lithium
b.
lanthanum
c.
beryllium
d.
helium
Hint
9.
An atom of an element contains eight electrons. What is the identity of this element?
a.
nitrogen
b.
oxygen
c.
carbon
d.
fluorine
Hint
10.
How do gamma rays differ from alpha particles and beta particles?
a.
Gamma rays have mass, whereas alpha and beta particles do not.
b.
Gamma rays and beta particles result in the formation of new atoms, but alpha particles do not.
c.
Alpha particle and beta particle emissions result in the formation of new atoms, whereas gamma ray emissions do not.
d.
Gamma rays and alpha particles result in the formation of new atoms, but beta particles do not.
Hint
11.
What is the primary factor in determining an atom’s stability?
a.
neutron to proton ratio
b.
proton to electron ratio
c.
neutron to electron ratio
d.
alpha particle to beta particle ratio
Hint
12.
What fundamental particle is identical to a beta particle?
a.
the positron
b.
the electron
c.
the neutron
d.
the proton
Hint
13.
How many protons are present in an atom potassium-39?
a.
19
b.
20
c.
39
d.
58
Hint
14.
What isotope has seven protons and six neutrons?
a.
carbon-7
b.
nitrogen-7
c.
nitrogen-13
d.
carbon-13
Hint
15.
What is the name for atoms of an element that have different masses?
a.
isomers
b.
alloforms
c.
allotropes
d.
isotopes
Hint
16.
The atomic number of an element is defined by its number of ________.
a.
neutrons
b.
electrons
c.
nuclei
d.
protons
Hint
17.
Which of the following particles has a mass that is almost the same as the mass of a proton?
a.
beta particle
b.
neutron
c.
electron
d.
positron
Hint
18.
What is the smallest particle of an element that maintains the properties of the element?
a.
molecule
b.
cation
c.
mixture
d.
atom
Hint
19.
Which of the following statements concerning hydrogen is false?
a.
All hydrogen isotopes have one neutron.
b.
All hydrogen isotopes have one proton.
c.
Hydrogen’s electron is not found in the nucleus.
d.
All hydrogen isotopes have one electron.
Hint
20.
Which of the following is a correct statement about a neutral atom?
a.
The atoms carry a positive or a negative charge.
b.
The atom has the same number of proton and electrons.
c.
Neutrons are present in the nucleus.
d.
The atom is radioactive.
Hint
