Begin with 3 free Unit 04 practice problems. When you want more reps on configurations, sublevels, orbital rules, and valence patterns, premium unlocks Quick Sets of 3, Standard Sets of 9, and Extended Sets of 18 from this 81-problem bank.
3 Free Sample Problems
A quick first pass: these 3 problems help you see whether the filling patterns make sense or still need a few slower, careful repetitions.
#4Valence Electrons
How many valence electrons does a nitrogen atom (N, Z = 7) have? Write the full configuration to verify.
#5Hund's Rule
Hund's Rule states that when filling orbitals of equal energy, electrons…
#6Quantum Numbers
Which set of quantum numbers (n, l, ml, ms) is NOT valid for any electron?
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81 practice problems in this unit bank
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Aligned to Unit 04 electron configuration
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