Name:  _____________________                              date:  __________________               period: _______

Ch. 3 atomic structure, isotopes                       test                   25 points                      chemistry

1. Fill-in the below table; the below atom / ion may not exist.  [13 points]

symbol

# protons

# neutrons

# electrons

charge

Atomic mass

57Fe +2

 

 

 

 

 

 

98

 

 

0

198

 

 

15

18

-2

 

2. A hypothetical sample contains ___   [7 points]

1,250  12C
750    13C
500    14C

isotopes; based on this information, what is the average atomic mass of carbon ?  show your work.

3.  What’s an isotope ?  Provide a (hypothetical ?) example to clarify your response.  [5 points]