To determine the sequence of increasing atomic numbers in Ne, Na+1, Mg+2, we need to compare the atomic numbers of these elements and their ions.
Ne refers to the element neon, which has an atomic number of 10.
Na+1 refers to the sodium ion, which is formed when a sodium atom loses one electron. The atomic number of sodium (Na) is 11, and since it loses one electron to become Na+1, the number of protons (and therefore the atomic number) remains the same. So, Na+1 also has an atomic number of 11.
Mg+2 refers to the magnesium ion, which is formed when a magnesium atom loses two electrons. The atomic number of magnesium (Mg) is 12, and since it loses two electrons to become Mg+2, the number of protons (and therefore the atomic number) remains the same. So, Mg+2 also has an atomic number of 12.
Therefore, the sequence of increasing atomic numbers is: Ne (10) < Na+1 (11) < Mg+2 (12).