Question

one mole of copper has a different mass from one mole of mercury because one mole of copper has a different mass from one mole of mercury because

Answer 1

I’m assuming you want to know why that is so...
They have a different mass because they’re made out of different materials and different materials vary in weight.

Answer 2

an atom of mercury has a different mass than an atom of copper.

Step-by-step explanation:

I took the exam and got it right.