Which of these is a chemical property of a substance?

A chemical property is a characteristic of a substance that may be observed when it participates in a chemical reaction. Examples of chemical properties include flammability, toxicity, chemical stability, and heat of combustion

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.