Atomic Structure
1. Fill in the table below using the information you learned about atomic structure
Symbol
C
Atomic #
Mass #
Protons
Electrons
Neutrons
11
53
U
P
12
82
F
80
H
Kr
25
Ag
16
N
Fe
Au
30
Ba
2 Here are three isotopes of an element
12
6 C.
13
6
C.
14
6. C
a. The element is _____________________
b. The number 6 refers to the _______________
c. The numbers 12,13,14 refer to _____________
d. How many neutrons are in the 1st isotope? ___________
e. How many neutrons are in the 2nd isotope ?____________
f. How many neutrons are in the 3rd isotope? _____________
3. Complete the following chart.
Isotope name Atomic #
Mass #
Uranium-235
Uranium-238
Boron-10
Boron-11
Proton
Electron
Neutron
4. Fill in the tables for each of the following isotopes. Some may require you to look up the
element name
Chromium58
Chromium63
# of Protons
# of protons
# of electrons
# of neutrons
48
51
# of neutrons
# of electrons
Selenium30
46
Selenium-35
# of protons
# of protons
25
# of neutrons
17
# of neutrons
15
# of electrons
# of electrons
5. Naturally occurring europium (Eu) consists of two isotopes with masses of 151 and 153.
Europium-151 has an abundance of 48.03% and Europium-153 has an abundance of 51.97%
what is the atomic mass of Europium?
6. Strontium consists of four isotopes with masses of 84( abundance of 0.50%), 86( abundance
of 9.9%) 87 ( abundance of 7.0%) and 88 ( abundance od 82.6%) Calculate the atomic mass of
strontium
7. Calculate the elemental atomic mass of Mg if the naturally occurring isotopes
are 24Mg, 25Mg and 26Mg. Their masses and abundances are as follows:
Isotope
Isotopic Abundance
24
Mg
78.70%
25
Mg
10.13%
26
Mg
11.17%
Atomic Mass
8. What is the atomic mass of hafnium if, out of every 100 atoms, 5 have a mass of 176, 19
have a mass of 177, 27 have a mass of 178, 14 have a mass of 179, and 35 have a mass of
180.0?
9 Calculate the average atomic mass of lithium, which occurs as two isotopes that have the
following atomic masses and abundances in nature: 6.017 u, 7.30% and 7.018 u, 92.70%.
10 Hydrogen is 99% 1H, 0.8% 2H, and 0.2% 3H. Calculate its average atomic mass.
11 Calculate the average atomic mass of magnesium using the following data for three
magnesium isotopes.
Isotope mass (u)
relative abundance
Mg-24
23.985
0.7870
Mg-25
24.986
0.1013
Mg-26
25.983
0.1117
12 Lithium has two naturally occurring isotopes: lithium-6 and lithium-7. If the average atomic
mass of lithium is6.941 amu, which isotope is the most abundant? How do you know
13 Rubidium is a soft, silvery-white metal that has two common isotopes, 85Rb and 87Rb. If the
abundance of 85Rb is 72.2% and the abundance of 87Rb is 27.8%, what is the average atomic
mass of rubidium?
Introduction to the periodic table
1. How are elements arranged on the Periodic Table?
2 List the alkali metals. What column can they be found in?
3 List the alkaline earth metals. What column can they be found in?
4 List the properties of metals
5 List the properties of nonmetals
6. Write the correct chemical symbol for the following elements. Remember that the first letter
of a chemical symbol is always capitalized and if there is a second letter in the symbol, it must
be lower case.
a. Copper _________. B. Sodium ___________ c Hydrogen _________ d. Silver ___________
7. Determine the number of atoms of each type of element is representee by the folulas for
the. Chemical compounds
A) SO2 S _________. O___________
B) FeCO3. Fe_______. C___________ O________
C) MgCl2. Mg________ Cl___________
D) Ca(OH)2 Ca________ O__________H___________
E) Zn(NO3)2. Zn_________ N________ O___________
F) (NH4)2SO4. N________ H_________ S____________ O__________
G) Al(ClO3)3. AL ________ Cl__________ O __________