Name:____________________
Date:____________
Period:___________
ISOTOPES WORKSHEET
There are 2 ways to represent isotopes:
1. Elements name-mass number
Example
lithium-7
2. Mass Number
7
Symbol
Atomic Number
Li
3
I. Using a periodic table, represent each of the following isotopes in the two ways shown above
1. 50 p+
72 n
50 e-
2. 21 e21 p+
25 n
3. 9 p+
9 e12 n
a)______________
a)______________
a)______________
b)______________
b)______________
b)______________
4. 14 n
15 e15 p+
5.
a)______________
a)______________
a)______________
b)______________
b)______________
b)______________
82 e127 n
82 p+
6. 140 n
88 p+
88 e-
II. The Isotopes of Hydrogen
7. How many isotopes does hydrogen have?_________
8. How are they all alike?_________________________________
9. List all three and give both types of representations.
a. ________________________________________________________________
b. ________________________________________________________________
c. ________________________________________________________________
Give the name of each isotope in these formats:
Carbon-12 and
12
C
6
1. 8 p+, 8 n0, 8 e-
______________________
and
__________
2. 14 p+, 14 n0, 14 e- ______________________
and
__________
3. 22 p+, 25 n0, 22 e- ______________________
and
__________
4. 78 p+, 117 n0, 78 e- ______________________ and
__________
5. 87 p+, 136 n0, 87 e- ______________________ and
__________
6. 40 p+, 51 n0, 40 e- ______________________
__________
and
What is the mass number in each of the following:
7.
60
Co _____
24
8.
27
Na _____
206
9.
11
Pb _____
10.
82
40
K _____
19
Determine the number of neutrons in the following:
11. carbon-14 _____
14.
60
Co _____
27
12. barium-139 _____
15.
24
Na _____
11
16.
206
13. lead-204 _____
Pb _____
82
17.
40
K _____
19
List the number of protons, neutrons, electrons, the atomic number Z, and the mass number for the
most common isotopes of the following elements:
18. Li
19. Mg
20. Hg
21. C
22. I
P __________
__________
__________
__________
_________
E __________
__________
__________
__________
_________
N __________
__________
__________
__________
_________
Z __________
__________
__________
__________
_________
A __________
__________
__________
__________
_________