MCQ
What idea states that lower energy level orbitals will be filled with electrons before higher energy level orbitals?
- APauli's exclusion principle.
- BOctet rule.
- CAufbau principle.
- DHund's rule.
Explanation:
Aufbau's rule/ principle states that the sub shell and orbitals of lower energy must be filled first before higher energy levels. The energy is proportional to (n + l) value.
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$\mathrm{HF}, \mathrm{H}_2, \mathrm{H}_2 \mathrm{~S}, \mathrm{CO}_2, \mathrm{NH}_3, \mathrm{BF}_3, \mathrm{CH}_4, \mathrm{CHCl}_3, \mathrm{SiF}_4$, $\mathrm{H}_2 \mathrm{O}, \mathrm{BeF}_2$
