Question

why are anions always larger than the atoms from which they are formed

Answer 1

Electrons added to the outer shell, all of them with a negative charge, means there are more repulsive forces, and that occupies more space.

Answer 2

why is the formula written for an ionic compound such as NaCl the empirtcal formula ,rather than a molecular formula?

Answer 3

thanks

Answer 4

Answered above.