<span>The correct answer is b. Boiling point, why? because the liquid sample of napthalene is heated and remained at the temperature of 218 degrees celsius, the outcome was that the napthalene was completely vaporized, therefore we are given the scenario that at the temperature of 218 degrees celsius is considered to be the boiling pont of napthalene.</span>
Answer: The atomic number is the number of protons in an atom of an element. In our example, krypton's atomic number is 36. This tells us that an atom of krypton has 36 protons in its nucleus.
