Standards:
 3.1.10 B Describe concepts of models as a way to predict and understand science and
technology.
 3.4.10 A Explain concepts about the structure and properties of matter.
Complete the following:
1. For each of the positive ions listed in column 1, use the periodic table to find in column 2
the total number of electrons that ion contains. The same answer may be used more than
once.
_B__ 1. Al+3
A. 2
_D__ 2. Fe+3
B. 10
_B__ 3. Mg+2
C. 21
_H__ 4. Sn+2
D. 23
_F__ 5. Co+2
E. 24
_E__ 6. Co+3
F. 25
_A__ 7. Li+1
G. 36
_C__ 8. Cr+3
H. 48
_G__ 9. Rb+1
I. 76
_I__ 10. Pt+2
J. 81
2. For each of the following ions, indicate the total number of protons and electrons in the
ion.
Ion
Number of Protons
Number of Electrons
Co+2
27
25
Co+3
27
24
Cl-1
17
18
K+1
19
18
S-2
16
18
Sr+2
38
36
Al+3
13
10
P-3
15
18
3. For each of the following atomic numbers, use the periodic table to write the formula
(including the charge) for the simple ion that the element is most likely to form.
a. 53
I-1
d. 88 Ra+2
b. 38
Sr+2
e. 9
c. 55
Cs+1
f. 13 Al+3
F-1
4. Write the chemical symbol for the ion with 12 protons and 10 electrons.
Mg+2
5. Write the chemical symbol for the ion with 74 protons and 68 electrons.
W+6
6. Write the chemical symbol for the ion with 95 protons and 89 electrons.
Am+6
7. Write the chemical symbol for the ion with 33 protons and 36 electrons.
As-3
8. Write the chemical symbol for the ion with 29 protons and 27 electrons.
Cu+2
9. How many protons, neutrons, and electrons are present in the 59Ni+2 ion?
28 p+ 31 no 26e-
28
10. How many protons, neutrons, and electrons are present in the 91Zr+4 ion?
40 p+
51no
36e-
40
11. How many protons, neutrons, and electrons are present in the 140Ce+3 ion?
58 p+ 82 no 55e-
58
12. How many protons, neutrons, and electrons are present in the 79Se-2 ion?
34 p+ 45 no 36 e-
34
13. How many protons, neutrons, and electrons are present in the 13C-4 ion?
6 p+
7 no
10 e-
6
14. Write the complete chemical symbol for the ion with 84 protons, 125 neutrons, and 80
electrons.
209
+4
84 Po
15. Write the complete chemical symbol for the ion with 27 protons, 32 neutrons, and 25
electrons.
59
+2
27 Co
16. Write the complete chemical symbol for the ion with 73 protons, 108 neutrons, and 68
electrons.
181
+5
73Ta
17. Write the complete chemical symbol for the ion with 31 protons, 39 neutrons, and 28
70
+3
electrons.
31 Ga