MCAT Flashcards: Ionization Energy

What is ionization energy? Ken Tao is an MCAT expert and explains that it’s the amount of energy required to remove an electron from an atom or ion. Ionization energy increases from left to right across the periodic table and decreases going down the periodic table.

Full Transcription

In this flash card video, we’re going to discuss “What is ionization energy?”

Ionization energy is the amount of energy required to remove an electron from an atom or an ion. Ionization energy increases as you go up and to the right of the periodic table. When you remove the first electron from an atom, the amount of energy required is called the first ionization energy.

If you want to remove a second electron, the amount of energy required to remove the second electron is called the second ionization energy.

You can continue on with the third, fourth, fifth, and so forth electron.

You should know that successive ionization energy is always requires more energy. This means that removing the second electron requires more energy than removing the first electron, and removing the third electron is going to require even more energy than removing the second electron. And you can continue that as you remove more and more electrons.