Lycoming College                                          Quiz 2                          Write Name on Back

Chem 110, 2002                                                                                             Upper Right


1.      Name the following elements:


Co_______________________         Cu___________________________


2.      Provide the symbol for each of the following:


silver_________________                  sulfur___________________


3.      The symbol for an ion of an element is


            a.         What element is it?  Symbol___________        Name________________________

b.                  How many protons are in its nucleus?___________________________________

c.                   How many neutrons are in its nucleus?__________________________________

d.                  How many electrons are in the ion?_____________________________________

e.                   Three isotopes of this element are known, with the following mass numbers and % abundance (in parentheses):      24(78.99%),      25(10.00%),             26(11.01%)

Calculate the average atomic mass for this element.  Show calculation.








4.      Name the following





5.      Provide formulas for

Ammonium dichromate____________________________________________________


Chromium(III) bromide___________________________________________________


6.   Comment briefly on how Daltonís atomic theory explains the Law of Constant Composition.