Posted by Carly on .
hi! this question confuses me.
"Pennies have mass of approximately 2.5 g. How many pennies are needed to make a mole of copper?"
if anyone can help, that would be amazing. <3
Thank you!

Chemistry 
DrBob222,
A mole of copper (if we take the average of all of the isotopes of copper) is about 63.5 grams. You can look up the exact atomic mass if you wish. So a mole of copper is 63.5 grams. How many pennies does it take to make 63.5 grams?

Chemistry 
Carly,
25.4.
Thank you so much! :)