ch. 3 & 4  atoms  & molecules   test   [30 points]                 honors Chemistry


Academic Honesty:   The answers on this test are my own and I am using only the allowed set of notes as described in the syllabus.  I have not discussed the test questions with anyone before or during the test nor have I seen the test questions prior to the exam.  If you violate any of the preceding items or do not sign, your semester grade is a F.


                                                                                                Signature:  ___________________


For problems involving calculations, show your work in an organized manner, include any relevant equation (or formula and conversion factor(s)), put the proper units in your calculations / answer, and have the proper number of significant figures in your answer. 



1.  fill-in the table.  [10 points]



# protons

# neutrons

# electrons


Atomic mass











+ 1




2.  fill-in the table  [10 points]


Chemical formula

Chemical name

Sodium carbonate








Tetra-silicon nona-iodide




3.  what is the average atomic mass of nitrogen if the % abundance of:  14N = 85%; 15N = = 10%; 17N = ?  [10 points]