A student investigated the diffusion of NH3, and HCl. Two sets of apparatus were set up as shown at room temperature and pressure. The damp red litmus paper for NH3 changed colour after 30 seconds. How long does it take for the damp blue litmus paper to change colour for HCl?

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.