The isotope with 13 protons and 14 neutrons is known as aluminum-27.
Explanation: The number of protons in an element determines its atomic number, which defines the element itself. In this case, having 13 protons means we are dealing with aluminum (Al), as aluminum has an atomic number of 13. The mass number of an isotope is calculated by adding the number of protons and neutrons. So, for this isotope, we have 13 protons + 14 neutrons = 27. Therefore, we name the isotope aluminum-27.