Compare the first ionization energy of Ca with that of Zn....

Compare the first ionization energy of Ca with that of Zn. Explain the difference in terms of the balance between shielding with increasing numbers of $\mathrm{d}$ electrons and the effect of increasing nuclear charge.

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Ionization Energy

Ionization energy is the amount of energy required to remove an electron from a neutral atom in its gaseous state. This property is influenced by the effective nuclear charge felt by the electron as well as the distance from the nucleus and the shielding provided by other electrons.

Effective Nuclear Charge

Effective nuclear charge is the net positive charge experienced by an electron after accounting for the shielding effect of other electrons. A higher effective nuclear charge means that electrons are held more tightly by the nucleus, resulting in a higher ionization energy.

Shielding Effect

The shielding effect refers to the reduction in the attractive force between the nucleus and an electron due to the presence of other inner electrons. As more electrons are added, particularly in inner shells or orbitals like d orbitals, the outer electrons experience less of the full nuclear charge, which can lower the ionization energy.

Role of d Electrons in Shielding

In elements with occupied d orbitals, these electrons contribute to the overall shielding effect but do so less efficiently than s or p electrons. Although increasing the number of d electrons can increase the shielding, the simultaneous increase in nuclear charge can compensate for this shielding, influencing the ionization energy in a non-linear way.

Please give Ace some feedback