Which of the following elements has the highest ionization energy? by Sunday | Mar 16 | Chemistry WAEC | 0 comments A. Calcium B. Chlorine C. Flourine D. Magnesium Correct Answer: Option D – Magnesium Users Also Read These:How are ionization energies related to the…The ionization energy is affected by the following…Which of the following substances has the highest…Which of the noble gases has the greatest ionization energy?Explain the meaning of Ionization energy. - NABTEB QUESTION