The Structure of the Atom
Practice Test
1.
What is the name for atoms of an element that have different masses?
a.
alloforms
b.
allotropes
c.
isomers
d.
isotopes
2.
Which of the following is not a fundamental particle in an atom?
a.
element
b.
neutron
c.
proton
d.
electron
3.
An atom of an element contains eight electrons. What is the identity of this element?
a.
oxygen
b.
carbon
c.
nitrogen
d.
fluorine
4.
The atomic number of an element is defined by its number of ________.
a.
neutrons
b.
protons
c.
electrons
d.
nuclei
5.
What is the charge of a gamma ray?
a.
1
+
b.
0
c.
2
+
d.
1
–
6.
What is the name for the emission of rays and particles by a radioactive material?
a.
radioactive series
b.
nuclear reactivity
c.
radiation
d.
decay
7.
What can you conclude from the deflection of a cathode ray in a magnetic field?
a.
The ray must be composed of charged particles.
b.
The ray must need to travel in a vacuum.
c.
The ray must be composed of iron.
d.
The ray must have a positive charge.
8.
Which of the following particles has a mass that is almost the same as the mass of a proton?
a.
electron
b.
positron
c.
neutron
d.
beta particle
9.
What is the charge of an alpha particle?
a.
1
–
b.
1
+
c.
0
d.
2
+
10.
What is the negatively—charged particle in an atom?
a.
positron
b.
electron
c.
proton
d.
neutron
11.
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.
Gamma rays and alpha particles result in the formation of new atoms, but beta particles do not.
d.
Alpha particle and beta particle emissions result in the formation of new atoms, whereas gamma ray emissions do not.
12.
Which scientist determined that almost all of an atom’s mass of is located in its nucleus?
a.
Democritus
b.
Thomson
c.
Rutherford
d.
a. Dalton
13.
Which of the following statements concerning hydrogen is false?
a.
Hydrogen’s electron is not found in the nucleus.
b.
All hydrogen isotopes have one neutron.
c.
All hydrogen isotopes have one electron.
d.
All hydrogen isotopes have one proton.
14.
Which of the following statements is correct?
a.
The nucleus is mostly empty space.
b.
A neutron will always be found orbiting the nucleus.
c.
An electron is about 2000 times more massive than a proton.
d.
A proton is about 2000 times more massive than an electron.
15.
How is the atomic mass unit (amu) defined?
a.
1/16 the mass of an oxygen-16 atom
b.
1/12 the mass of a carbon-12 atom
c.
1/14 the mass of a nitrogen-14 atom
d.
1/13 the mass of a carbon-13 atom
16.
What is the smallest particle of an element that maintains the properties of the element?
a.
atom
b.
mixture
c.
molecule
d.
cation
17.
What is the charge of a beta particle?
a.
2
+
b.
0
c.
1
+
d.
1
–
