Key idea
Ionization energy
Ionization energy is the energy required to remove an electron from a gaseous atom or ion in a specified state. Successive ionization energies refer to successive electron removals.
Ionization energy
The key idea
Ionization energy is the energy required to remove an electron from a gaseous atom or ion in a specified state. Successive ionization energies refer to successive electron removals.
Why it matters
Its periodic pattern is powerful but not perfectly smooth because subshell structure, pairing and shielding matter.
A picture to remember
Key idea
Ionization energy
Guided example
Ionization energy
Ionization energy is the energy required to remove an electron from a gaseous atom or ion in a specified state. Successive ionization energies refer to successive electron removals.
Put it into practice
Ionization energy
Choose a concrete case linked to Ionization energy. Write down the known information, what you are trying to find, and the units. Then state the rule, model or trend you will use. If a calculation is involved, keep the units visible at every line; if it is conceptual, state what changes and what remains fixed.
Check your answer
A strong answer contains four things: the starting situation, the variable that changes, the direction or numerical result, and one check. The check can be a unit, an order of magnitude, a limiting case or a comparison with a familiar example.