Final answer:
The electron configurations for carbon, nitrogen, oxygen, and hydrogen are 1s²2s²2p², 1s²2s²2p³, 1s²2s²2p´, and 1s¹ respectively. These configurations reflect how each element's electrons are distributed across different energy levels and orbitals, following the rules of filling orbitals (Aufbau principle) and maximizing unpaired electrons (Hund's rule).
Step-by-step explanation:
The question concerns the electron configuration of the second-row elements in the periodic table, namely carbon (C), oxygen (O), nitrogen (N), and hydrogen (H). The electron configuration for these elements is particularly important because it determines how these atoms interact with other atoms and how they bond to form molecules.
Electron Configurations:
Carbon (C): 1s²2s²2p². Carbon has a total of six electrons. The first two fill the 1s orbital, the next two fill the 2s orbital, and the last two are in the 2p orbital, following Hund's rule, which states that electrons will occupy separate orbitals before pairing up.
Nitrogen (N): 1s²2s²2p³. Nitrogen atoms have seven electrons; after filling the 1s and 2s orbitals, they place one electron in each of the three p orbitals.
Oxygen (O): 1s²2s²2p´. Oxygen atoms have eight electrons; following the 1s and 2s orbitals being filled, they have four electrons in the 2p orbitals with one pair and two unpaired electrons.
Hydrogen (H): 1s¹. Being the simplest element, hydrogen has just one electron in the 1s orbital.