When can the fourth and third energy shells hold more?

4th Shell4s, 4p, 4d, 4f2 + 6 + 10 + 14 = 32

elements make up everything, and they combine to make compounds.

the answer is c

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.