to find the atomic mass of an element that is included on a periodic table, what must be found first? a. the number of protons in that element. b. the number of electrons in that element. c. the number of neutrons in that element. d. the average mass of all the isotopes.

D the average mass of all the isotopes

Explanation:

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.