Which of the following elements has the lowest first ionization energy?A.Scandium (Sc)B.Oxygen (O)C.Phosphorus (P)D.Strontium (Sr)SUBMITarrow_backPREVIOUS

The element with the lowest first ionization energy among Scandium (Sc), Oxygen (O), Phosphorus (P), and Strontium (Sr) is Strontium (Sr).

Here's why:

Ionization energy is the energy required to remove an electron from an atom or ion. The trend in the periodic table is that ionization energy increases from left to right across a period and decreases down a group.

Looking at the periodic table, Strontium (Sr) is located further down and to the left compared to the other elements listed. Therefore, it has the lowest first ionization energy.