name: _______________
date: _______
the structure of the atom
1. The 3 main particles of the atom are:
!
a. __________
b. __________
c. __________
2. Their respective electrical charges are:
!
a. __________
b. __________
c. __________
3. The number of protons in one atom of an element determines the atom’s __________, and the number of electrons
determines __________ of an element.
!
4. The atomic number provides the number of __________ in one atom of an element, and also the number of __________
in a neutral atom of the element.
!
5. The __________ of an element is the average mass of an element’s naturally occurring isotopes, taking into account
the __________ of each isotope.
!
!
6. The __________ of an element is the total number of protons and neutrons in the__________ of the atom.
7. Provide the atomic number for:
a .lithium, Li
__________
b. iron, Fe
__________
c. oxygen, O
__________
d. krypton, Kr
__________
e. bromine, Br __________
f. copper, Cu
__________
h. helium, He
__________
i. gallium, Ga
__________
b. boron, B
__________
c. antimony, Sb __________
e. iodine, I
__________
f. xenon, Xe
g. mercury, Hg __________
8. Provide the number of electrons in a neutral atom of:
a. uranium, U
__________
d. chlorine, Cl __________
__________
9. Provide the complete atomic or ionic symbol for the element which contains the following particles: a. 26 electrons, 29 neutrons, 26 protons ___
b. 20 protons, 20 neutrons
___
c. 53 protons, 74 neutrons
d. 80 electrons, 125 neutrons, 82 protons
___
f. 0 neutrons, 1 proton, 1 electron
___
___
e. 2 neutrons, 2 electrons (neutral atom) ___
!
10. Can an element be identified based only upon the following information:
a. number of protons
___
c. number of electrons in a neutral atom
___
b. number of neutrons
___
d. number of electrons
___ 11. Fill in the missing items in the table below, using the element symbols above as reference:
!
element name silver-108
Z
A
p+
en0
symbol
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
tungsten-183
krypton-84
phosphorus-31 iron-56
iodine-126
name: suggested answers
date: _______
the structure of the atom
1. The 3 main particles of the atom are:
!
a. proton
b. neutron
c. electron
2. Their respective electrical charges are:
!
a. positive
b. negative
c. neutral
3. The number of protons in one atom of an element determines the atom’s atomic number, and the number of electrons
determines the charge of an element.
!
4. The atomic number provides the number of protons in one atom of an element, and also the number of electrons in a
neutral atom of the element.
!
5. The mass number of an element is the average mass of an element’s naturally occurring isotopes, taking into account
the atomic mass of each isotope.
!
!
6. The mass number of an element is the total number of protons and neutrons in the nucleus of the atom.
7. Provide the atomic number for:
a .lithium, Li
3
b. iron, Fe
26
c. oxygen, O
8
d. krypton, Kr
36
e. bromine, Br 35
f. copper, Cu
29
h. helium, He
2
i. gallium, Ga
31
b. boron, B
5
c. antimony, Sb 51
e. iodine, I
53
f. xenon, Xe
g. mercury, Hg 80
8. Provide the number of electrons in a neutral atom of:
a. uranium, U
92
d. chlorine, Cl 17
54
9. Provide the complete atomic or ionic symbol for the element which contains the following particles: 55
a. 26 electrons, 29 neutrons, 26 protons ! 26
Fe
c. 53 protons, 74 neutrons
!
! 127
53 I
e. 2 neutrons, 2 electrons (neutral atom) ! 42 He
b. 20 protons, 20 neutrons
! 40
20 Ca
d. 80 electrons, 125 neutrons, 82 protons
2+
! 207
82 Pb
f. 0 neutrons, 1 proton, 1 electron
! 11H 10. Can an element be identified based only upon the following information:
a. number of protons
Y
c. number of electrons in a neutral atom
Y
b. number of neutrons
N
d. number of electrons
N
11. Fill in the missing items in the table below, using the element symbols above as reference:
!
element name silver-108
tungsten-183
krypton-84
phosphorus-31 iron-56
iodine-126
Z
47
74
36
15
26
53
A
108
183
84
31
56
126
p+
47
74
36
15
26
53
e-
47
74
36
15
26
53
n0
61
109
48
16
30
73
symbol
Ag
W
Kr
P
Fe
I
!
!
!