Copper has Cu2+ atoms arranged in layers and held together by a sea of electrons in lattice form. The sea of electrons or de-localized electrons are provided by Cu. Each copper atom contributes 2 electrons to the sea for binding of Cu2+ atom layer.
The sea of electrons are highly mobile and require a very small potential difference across the atoms to push these electrons to form a current. The mobility, ease and freeness of these electrons allows copper to be a good electrical conductor
b. the valence electrons from the s and p orbitals of the interacting metal atoms delocalize. That is to say, instead of orbiting their respective metal atoms, they form a “cloud” of electrons that surrounds the positively charged atomic nuclei of the interacting metal ions.
c. due to the presence of free electrons in its outer energy levels
Since, the spheres are of same size and rotational speed of the sphere are not dependent on their masses. So, both the sphere will reach the bottom of the at the same time with the same speed. But their kinetic energies are different.
