Is sugar (c6h12o6) and oxygen gas (o2) combine to form carbon dioxide (co2) and water (h2o) a chemical reaction?

The answer to your question is Yes, it is a chemical reaction

Explanation:

A chemical reaction is a process that involves a rearrangement of the atoms and molecules of the reactants to form products.

In your question, sugar and oxygen are transformed into carbon dioxide and water that process is the definition of a chemical reaction.

Reaction

                    C₆H₁₂O₆   +  9O₂   ⇒  6CO₂   +   6H₂O

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.