ATOMIC STRUCTURE WORKSHEET
Name
1. Complete the table. There is enough information given for each element to determine all missing numbers.
Symbol / Atomic Number / Mass Number / Number of Protons / Number of Electrons / Number of Neutrons23Na1+
K1+ / 40
13 / 11 / 15
F1- / 10
26 / 51 / 25
50 / 50 / 72
131I1-
26Mg2+
109 / 47 / 46
1 / 2 / 1
36S / 18
26 / 23 / 25
27Al / 10
2 / 4 / 2
Cr / 53
2. Identify two different ions of the same isotope of the same element. What do they have in common? What is different?
3. Identify two different isotopes of the same element? Are these two atoms or ions?
4. Draw two symbols for different ions of different isotopes of the same element?
5. Sketch a picture of a Carbon 13 (4- ion), showing the location of all subatomic particles.
6. The number of protons in one atom of an element determines the atom’s ______, and the number
of electrons determines the ______of the element.
7. The atomic number tells you the number of ______in one atom of an element. It also tells
you the number of ______in a neutral atom of that element. The atomic number gives the
“identity” of an element as well as its location on the periodic table. No two different elements will have the
______atomic number.
8. The ______of an element is the total number of protons and neutrons in the ______of the atom.
9. The mass number is used to calculate the number of ______in one atom of an element. In order
to calculate the number of neutrons you must subtract the ______from the
10. If you know ONLY the following information can you ALWAYS determine what the element is? (Yes/No)
a. Number of protons ______
b. Number of neutrons ______
c. Number of electrons in a neutral atom ______
d. Number of electrons ______
11. While every element is ______(different or the same) from every other element…each element is
made up of ______which are ______(different or the same)
between one element and another.