What happens when magnesium or manganese is treated with very dil HNO3​

Metals also react with nitric acid, but hydrogen gas is not evolved, because nitric acid is a strong oxidising agent. So, it oxidises the hydrogen to water and itself gets reduced to any nitrogen oxide. However, magnesium and manganese react with dilute nitric acid to evolve hydrogen gas.

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.