Final answer:
The statement is false; an atomic orbital can hold only two electrons with opposite spins, according to the Pauli exclusion principle.
Step-by-step explanation:
The statement "As many as four electrons can occupy the same orbital" is false. According to the Pauli exclusion principle, an atomic orbital can hold a maximum of two electrons, and these electrons must have opposite spins. This principle is a fundamental rule in quantum mechanics, proposed by Wolfgang Pauli. Taking oxygen as an example, it has four 2p electrons. In the 2p subshell, there are three orbitals, and these 2p electrons will occupy the orbitals in a way that each orbital gets one electron first before any orbital gets a second electron. When a fourth electron is placed in an orbital, it pairs up with one of the electrons already present, but with an opposite spin.
The electronic configuration of oxygen demonstrates this principle, as once each of the three 2p orbitals has a single electron, the fourth electron can pair up in one of these orbitals, assuming an opposite spin to the electron already present.
In summary, the orbital capacity is limited to two electrons, each with a different spin quantum number (± ½).