50 Identify & Predict
Materials: Element Cards Table, Bohr Models Table, and Ziploc bag with 11 Bohr Models.
Part 1:
Instructions: Use the Table with the Element Cards already sorted to answer the questions.
Questions:
1. Write down at least two patterns that you can observe.
2. Focus on the two Magnesium cards. What do the two cards have in common?
3. What do the two cards have different?
4. Because the masses of the atoms are the same (24 amu) this means that the element and its ion have
the same number of protons and neutrons. Then what must be different between the element and its
ion?
5. Does the mass of an atom change when it becomes an ion, yes or no.
6. Please grab a blank periodic table. Locate each of the elements that you have cards of: write their
chemical symbol in the box and color them in. Color the positively charged (1+, 2+ or 3+) elements red
and the negatively charged (1-, 2-, or 3-) elements blue.
7. Are metals usually positively charged or negatively charged?
8. Are nonmetals usually positively charged or negatively charged?
9. Were there any ions of the noble gases, yes or no? Why do you think that the noble gases do not form
ions?
Please have Mrs. Sanchez or Ms. Huffman check your answers before moving on to Part 2.
Part 2:
Instructions: Use the table of Bohr Model Cards to answer the questions.
Questions:
10. Look at the valence electrons in the elements and their ions. Notice that, in Lithium, the atom has lost
an electron. While Fluorine has gained an electron. Please write down the differences for the rest of
the elements:
a. Be:
b. Na:
c. Mg:
d. O:
e. S:
f. Cl:
11. Because Lithium lost 1 negative electron, it now has a charge of 1+. Fluorine gained 1 negative electron
so it now has a charge of 1-. If Calcium loses 2 electrons, what will its charge be?
Now take out the bags with the Bohr Models of ions and noble gases. Group those cards into three groups,
sorted by number of shells and how many valence electrons each ion or noble gas has.
12. For each of these ions, write down which Noble gas the ion has the same number of valence electrons
as:
a. Li1+:
b. Be2+:
c. Na1+:
d. Mg2+:
e. O2-:
f. F1-:
g. S2-:
h. Cl1-:
13. Why do elements’ ions have the same number of valence electrons as the noble gases?
Now remove the Noble Gases and arrange the ions into two different groups, sorted by whether the ion
is positive or negative.
14. The ions with a positive charge are called CATIONS (CAT-EYE-ONS). Atoms become cations when they
lose electrons (become more positive). List the 4 ions that have a positive charge and are called
cations. Follow this format: Na1+
15. The ions with a negative charge are called ANIONS (AN-EYE-ONS). Atoms become anions when they
gain electrons (become more negative). List the 4 ions that have a negative charge and are called
anions. Follow this format: Cl116. Use the periodic table that you colored in Question #6, please list all of the element cards that are
cations and their charges. Then list all of the element cards that are anions and their charges.
More questions:
17. What kind of ion will Strontium form? (cation or anion)
18. What kind of ion will Selenium form? (cation or anion)
19. Alkali metals will:
a. Gain or lose electrons?
b. How many electrons will they gain or lose?
c. Will they form cations or anions?
20. Halogens will:
a. Gain or lose electrons?
b. How many electrons will they gain or lose?
c. Will they form cations or anions?
21. Please draw the Bohr Model for Potassium (K) and its ion.