[afnan]

I HAVE THIS HOME WORK I CANT DO IT PLEASE HELP ME

The element of Copper is found to be contain the two isotopes 63Cu and 65Cu whose masses have been determined to be 92.9298 and 64.9278 amu respectively, calculate the average atomic mass of copper?





ALSO



During the experiment of determine charge of electron,  the resulted charge/mass ratio was = 9.58 x 104  c/g, calculate the mass of this particles if you know that its charge was (e) = 3.2 x 10-19 coulombs.




                                     I would appreciate your cooperation

[sjb]

I'm getting a strange feeling of deja lu here See http://www.chemicalforums.com/index.php?topic=40304.msg154118 ?