Name
Date
Period
Workbook Activity
50
Chapter 8, Lesson 3
Atomic Number and Mass Number Directions Answer each question on the lines. Use complete sentences. 1. An isotope is an atom with a different ______. A number of electrons C number of neutrons B number of protons D charge 2. Changing the number of protons makes an atom _______. A an isotope C an ion B a new element D stay the same 3. Changing the number of electrons makes an atom _______. A an isotope B a new element C an ion
D stay the same
4. A chlorine atom has a 1– charge. This atom has ______ electrons. A 16 B 17 C 18
D 19
5. The ion 11Na1⁺ has _____ protons and _____ electrons. A 10, 11 B 10, 10 C 11, 10
D 11, 11
6. Mass number is the number of ______ and ______ in an atom. A protons, neutrons C neutrons, electrons B protons, electrons D isotopes, ions
Directions The table shows information about isotopes. Complete the table. Isotope Name Carbon-14
Isotope Symbol 14 6C 4 1 Li ⁺ 3
10. 13.
14.
Atomic Number
Mass Number
7.
8.
3 5
11.
3 9
© Pearson AGS Globe. Permission is granted to reproduce for classroom use only.
08_662_Chem_TRL_WA.indd 3
Number of Number of Number of Protons Neutrons Electrons 9. 6 6 5
1 15.
12.
5
Chemistry
3/28/06 4:06:34 PM