1. Ionization enthalpy increases across a period due to increased nuclear charge.
2. The anomaly: B \(<\) Be because Be has a fully filled $2s^2$ configuration, making it more stable.
3. Final order: Li \(<\) B \(<\) Be \(<\) C \(<\) N.
List I | List II | ||
---|---|---|---|
A | Mesozoic Era | I | Lower invertebrates |
B | Proterozoic Era | II | Fish & Amphibia |
C | Cenozoic Era | III | Birds & Reptiles |
D | Paleozoic Era | IV | Mammals |