GENERAL KNOWLEDGE

Detailed explanation-1: -Orbital: A region of space within an atom where an electron in a given subshell can be found. Any orbital can hold a maximum of 2 electrons with opposite spin. The first shell has one 1s orbital and holds 2 electrons. The second shell holds 8 electrons; 2 in a 2s orbital and 6 in three 2p orbitals.

Detailed explanation-2: -For example, energy level I can hold a maximum of two electrons, and energy level II can hold a maximum of eight electrons. The maximum number depends on the number of orbitals at a given energy level.

Detailed explanation-3: -Each type of orbital can accommodate a different number of electrons. According to the electron cloud model, the first energy level (numbered 1) only has one s orbital. Therefore, it can only hold a maximum of two electrons. S orbitals are approximately spherical.

Detailed explanation-4: -The first principal energy level contains only an s sublevel; therefore, it can hold a maximum of two electrons.

Detailed explanation-5: -Pauli’s Exclusion Principle states that no two electrons in the same atom can have identical values for all four of their quantum numbers. In other words, (1) no more than two electrons can occupy the same orbital and (2) two electrons in the same orbital must have opposite spins (Figure 46(i) and (ii)).