In a sample of pure copper, all atoms have atomic numbers which are..
A) the same and the atoms have the same number of electrons
B) the same but the atoms have a different number of electrons
C) different but the atoms have the same number of electrons
D) different and the atoms have a different number of electrons
D. Atomic #'s change depending upon the element and same with the electron field number, they change accordingly. Periodic Table tells you all this
The correct answer is A. Its pure copper so all the elements are COPPER! That is all it is made of because its PURE copper. Also if it has the same atomic number the number of electrons has to be the same.Source(s): chemistry textbook