#1: What do the elements Be, Mg,
and Ca all have in common?
2 valence electrons
2. Draw a shell model (like those given
in the activity) for Rb, Rubidium.
Identify the core and valence
electrons.
Valence
1e
electron
18e
-
-
8e-
2e-
8e-
Core electrons
#3: Compare the elements carbon, C,
and silicon, Si.
a. How many electrons does an atom of each of
these elements have? C: 6 electrons Si: 14 eb. Draw shell models for each of these elements.
2e- 4e
-
8e2e-
Carbon
Silicon
4e-
c. How many valence electrons do atoms of
each of these elements have? 4 electrons
d. How many core electrons do atoms of each
of these elements have? C: 2, Si: 10
e. Carbon and silicon have similar properties –
why do you think this is?
Same number of valence
electrons
#4: Provide the following information
for the element with the atomic
number 17.
a. The element’s name, symbol, and
family/group#. Chlorine, Cl, Halogens/VIIA
b. The number of protons in the nucleus. 17
c. The number of neutrons in the nucleus.
Explain how you determined this.
18, Mass number (35) minus Atomic number
d. The number of electrons in a neutral atom of
this element.
17
e. The number of valence electrons. 7
f. The number of core electrons. 10
g. The names of 3 other elements with the
same number of valence electrons.
Fluorine, Bromine, Iodine, Astatine
#5: Answer problem #4 questions a-g,
for the element with the atomic
number 50.
a. The element’s name, symbol, and
family/group #. Tin, Sn, IVA
b. The number of protons in the nucleus.
c. The number of neutrons in the nucleus.
Explain how you determined this.
50
69, Mass number (119) minus Atomic #
d. The number of electrons in a neutral atom of
this element.
50
e. The number of valence electrons. 4
f. The number of core electrons. 46
g. The names of 3 other elements with the
same number of valence electrons.
Carbon, Germanium,
Lead, and Silicon