Concept Explanation: Ionization Enthalpy and Isotopes

Ionization enthalpy is the energy required to remove the most loosely bound electron from an isolated gaseous atom. It depends on the atomic structure, particularly the nuclear charge and the distance of the electron from the nucleus.

The given atoms are isotopes of carbon: ${}^{12}C_6$ and ${}^{14}C_6$.

Step 1: Understand Isotopes

Isotopes are atoms of the same element with the same atomic number (number of protons) but different mass numbers (different number of neutrons).

For ${}^{12}C_6$: Atomic number (Z) = 6, Number of neutrons = 6

For ${}^{14}C_6$: Atomic number (Z) = 6, Number of neutrons = 8

Step 2: Analyze Factors Affecting Ionization Enthalpy

Ionization enthalpy depends on:

• Nuclear charge (number of protons)
• Atomic size (distance of electron from nucleus)
• Shielding effect by inner electrons

Since both isotopes have the same atomic number (6 protons), they have:

• Same nuclear charge
• Same electron configuration: 1s² 2s² 2p²
• Same number of electrons (6)
• Same atomic size (neutrons don't significantly affect electron cloud distribution)

Step 3: Compare the Ionization Enthalpies

The difference in neutron number affects mass but not the electronic structure or nuclear charge. Therefore, the ionization enthalpies of isotopes are:

$\mathrm{Almost}\mathrm{the}\mathrm{same}$

Final Answer

The ionization enthalpies of ${}^{12}C_6$ and ${}^{14}C_6$ are almost same.

Related Topics

• Isotopes and their properties
• Periodic trends in ionization enthalpy
• Atomic structure and electronic configuration
• Nuclear charge and effective nuclear charge

Important Formulae and Theory

Ionization Enthalpy: The minimum energy required to remove an electron from an isolated gaseous atom in its ground state.

First ionization energy: $X\left(g\right)\to X^{+}\left(g\right)+e^{-}$

Factors affecting ionization enthalpy:

• Nuclear charge: Increases with increasing atomic number
• Atomic size: Decreases with decreasing atomic radius
• Shielding effect: More inner electrons reduce ionization energy
• Stability of half-filled and fully-filled orbitals

Isotopes: Atoms of the same element with same atomic number but different mass numbers. They have identical chemical properties but different physical properties related to mass.