Atoms and Period Table Quiz

a. number of isotopes b. location on the periodic table. c. number of neutrons d. atomic mass. 18. An atom with the same number of protons, but a different number of neutrons is called a(n)___. a. isotope b. ion c. isomer d. iodine. 19. The first shell in an atomic drawing can hold a maximum of __ electrons. a. 2 b. 4 c. 6 d. 8. 20. ................
................