Question

Each period in the periodic table starts with a s-subshell of the new shell and ends with filling of (1) Same subshell (2) p-subshell of the same shell (3) p-subshell of the next shell (4) d-subshell of the same shell

Short answer

p-subshell of the same shell.

Step-by-step solution

Understanding the Period (Row) in the Periodic Table

Each period in the periodic table starts with elements filling the s-subshell of a new electron shell.

Determine the Ending Subshell

To identify which subshell ends a period, observe the elements at the far right of the periodic table, known as noble gases.

Characterize the Ending Subshell in a Period

Noble gases are characterized by a complete p-subshell, indicating that the period ends with the filling of the p-subshell of the same shell.

Confirm the Correct Option

Based on the observation, the period ends with filling the p-subshell of the same shell.

Key concepts

s-subshell

The s-subshell is the first electron subshell in each electron shell of an atom. It can hold up to 2 electrons. The position of elements in the periodic table is determined based on which subshell their outermost electrons fill. For instance, the first element in a period fills the s-subshell. Elements in the same group often share similar properties because they have a similar outer electron configuration. The s-subshell is always spherical.

Electron Shell

An electron shell is a group of atomic orbitals with the same principal quantum number, n. Each shell can hold a specific number of electrons, following the formula 2n^2. Shells are organized into subshells, including s, p, d, and f types, each with a distinct shape and capacity. The first shell (n=1) has only one s-subshell, while the second shell (n=2) includes both an s and a p-subshell. Electron shells determine the atom's radius and are critical in understanding chemical bonding and properties.

Noble Gases

Noble gases are found in Group 18 of the periodic table and are characterized by having full electron shells. This makes them very stable and inert, meaning they rarely react with other elements. Noble gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). The stability of noble gases comes from their completely filled p-subshells, which give them a full complement of valence electrons. Because they end each period, they play a key role in understanding the periodic table structure.

p-subshell

The p-subshell is one of the types of electron subshells that exist starting from the second electron shell (n=2) onwards. It can hold up to 6 electrons across three p-orbitals. Each p-orbital can hold a maximum of 2 electrons. As you move across a period from left to right, after filling the s-subshell, electrons start filling the p-subshell. The p-block elements of the periodic table include groups 13 to 18, ending with the noble gases. The filling of the p-subshell completes the electron configuration of the elements in each period.