why did magnesium (Mg) get a bigger electronegativity than aluminium(Al) (same period)? andwhy did the magnesium(Mg) get a bigger electronegativity than calcium (Ca) (same group)Thanks.
Electronegativity is defined as the ability of an atom i a molecule to attract electrons to itselfAluminum has a higher electronegativity than magnesium because of its higher electron affinityAluminum has a higher electron affinity because it has one electron it its 3p subshell, making it relatively easy to gain another electron; hence it has a higher electronegativityMagnesium, on the other hand, has full 3s subshell, and has to put the next electron in a 3p orbital, which is higher in energy, and requires energy to put an electron in thereThus, it has a positive electron affinity, and thus, a lower electronegativity than aluminumSimilarly, ionization energies tend to decrease as we move down a group on the periodic table; in this case it is magnesium and calciumCalcium has a lower ionization energy, and thus, tends to lose electrons more readily compared to magnesium, and thus, as a consequence, magnesium would have to have a higher electronegativity than calcium because it is harder to add electrons to calcium than for magnesium.
