Question
From each set, choose the atom which has largest ionisation enthalpy and explain your answer:
- F, O, N
- Mg, P, Ar
- B, Al, Ga
✓
Answer
- F has highest ionisation enthalpy due to smallest atomic size, therefore, highest effective nuclear charge because it has 9 protons, O has 8 protons and N has 7 protons.
- Ar has highest ionisation enthalpy due to stable electronic configuration.
- B has highest ionisation enthalpy due to smallest atomic size and, therefore, highest effective nuclear charge, has two shells only. Al has 3 shells, Ga has 4 shells.
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