Answers to Worksheets –
Review for Quiz
1. Section 3-3 Practice
Problems - ANSWERS
State the number of proton, neutrons, and electrons in the following:
1. Vanadium
2. Nitrogen
3. Argon
4. Potassium
5. Platinum
p+=_____
p+=_____
p+=_____
p+=_____
p+=_____
no=_____
no=_____
no=_____
no=_____
no=_____
e-=_____
e-=_____
e-=_____
e-=_____
e-=_____
An element has the same number of protons as electrons.
(#p+ = #e- for an element)
The atomic mass of an element or an ion is the # of p+ + # of no
(At. Mass= #no + #p+)
Name the following elements:
6. 5 protons
7. 17 protons
8. 25 protons
9. 82 protons
10. 92 protons
______
______
______
______
______
The atomic number of an element is the
number of protons, which identifies the
element or ion
Write the following complete chemical symbols:
11. Ion with 12 protons and 10 electrons
______
12. Ion with 74 protons and 68 electrons
______
13. Ion with 95 protons and 89 electrons
______
14. Ion with 33 protons and 36 electrons
______
15. Ion with 29 protons and 27 electrons
______
An ion is a charged particle (single atom or group of atoms).
The ion is charged b/c there is differing number of e- and p+
The # p+ - #e- = charge number for a single atom ion
i.e. 8 p+ and 10e- = 168O2-
2. 3-4 Practice Problems ANSWERS
1. Alpha:
2. Beta:
3. Alpha:
4. Beta:
5. Alpha:
6. Alpha:
7. Beta:
8. Alpha:
9. Beta:
10.Beta:
231 Pa
91
223 Fr
87
149 Sm
62
165 Pm
61
249
101Md
146 Sm
62
198 At
85
150 Gd
64
152 Xe
54
120 Cs
55
 _____
 _____
 _____
 _____
 _____
 _____
 _____
 _____
 _____
 _____
+
+
+
+
+
+
+
+
+
+
______
______
______
______
______
______
______
______
______
______
3. Chapter 3 review
questions (part 1):
1. What is the mass number of isotope X in the figure above? 77
2. What is the charge of the ion of isotope X in the figure above?
10+
3. In the figure above what is the number of electrons in the ion of
isotope Y? 36
4. Using a periodic table, how many protons, neutrons, and
Isoto
pe
electrons are there in an ion of Ba2+?p = 56, n= 81, e=54
Balance the following nuclear equations. Be sure to give the
symbol, with superscript and subscript, for the missing nucleus or
particles.
5. Beta decay
202Hg
80
 Beta +___20281 Tl_
6. Alpha decay
195
191 Os_
Pt

Alpha
+____
78
76
Atomic Mass # of # of
# of Char
Numbe Numb proto neutr electr ge
r
er
ns
ons
ons
X
38
77
38
39
28
10+
Y
35
76
35
41
36
1-
4. Chapter 3 review
questions (part 2)
11
5B
21
11
1+
Na
3. List the number of:
39 K+1
19
Protons __19__
Neutrons __20__
Electrons _18___
4. List the number of:
33 S
16
Protons __16__
Neutrons _17___
Electrons __16__
9. Explain why the atomic mass
is a decimal point and not a
whole number. Isotope percent
of Abundance on Earth
10. Describe what change is
occurring to the Calcium atom
when this ion is being formed:
Ca2+
Change in electrons
2 less, thus 2 positive charges
11. What about the atomic structure of these particles causes them to be deflected
by the plates?
A: attracted to + so has – charge (beta)
B: no attraction so no charge (gamma)
C: attracted to – so has a + charge (alpha)
12.
Isotope
Atomic
Number
Mass
Number
# of
protons
# of
neutrons
# of
electrons
Charge
L
30
66
30
36
28
2+
M
35
80
35
45
36
-1
13. Beta decay:
35
14. Alpha decay:
0 e + 35
S

16
117 Cl
210
84
Po  2He
4
206
+
82
Pb