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Question: Write the correct ground-state electronic configuration for a Nitrogen atom (Atomic number Z = 7) by applying the Aufbau principle, Pauli exclusion principle, and Hund's rule. Step 1: Determine the total number of electrons. For a neutral Nitrogen atom, the atomic number is 7, so it has 7 electrons. Step 2: Apply the Aufbau principle to fill orbitals in order of increasing energy. The energy order is 1s, then 2s, then 2p. Fill the lowest energy 1s orbital first with its maximum capacity of 2 electrons. Configuration so far: 1s2. Electrons remaining = 7 - 2 = 5. Step 3: Fill the next lowest energy orbital, which is 2s, with its maximum capacity of 2 electrons. Configuration so far: 1s2 2s2. Electrons remaining = 5 - 2 = 3. Step 4: Place the remaining 3 electrons into the 2p orbitals. Since there are three degenerate 2p orbitals (2px, 2py, 2pz), apply Hund's rule. Instead of pairing them up, put one electron into each of the three empty 2p orbitals with parallel spins. Configuration becomes: 1s2 2s2 2px1 2py1 2pz1, which is normally written compactly as 1s2 2s2 2p3. Step 5: Verify the Pauli exclusion principle by checking that every orbital containing two electrons has them spinning in opposite directions (represented by opposite arrows, one pointing up and one pointing down). The final correct electronic configuration for Nitrogen is 1s2 2s2 2p3.