**Explanation:**

The location of an element in the periodic table is determined by its electron configuration, which is determined by the **quantum numbers**.

**1. Quantum Numbers:**
Quantum numbers are a set of four numbers that describe the properties of an electron in an atom. These numbers include:

- **Principal Quantum Number (n)**: Determines the energy level or shell of the electron.
- **Azimuthal Quantum Number (l)**: Determines the shape of the orbital.
- **Magnetic Quantum Number (m)**: Determines the orientation of the orbital in space.
- **Spin Quantum Number (s)**: Determines the spin state of the electron.

**2. Filled Last Orbital:**
The filled last orbital refers to the orbital that contains the highest energy electrons in an atom. This orbital is often referred to as the valence shell or outermost shell.

**3. Determining the Location:**
The location of an element in the periodic table is determined by the electron configuration, which is described by the quantum numbers. The filled last orbital is determined by the principal quantum number (n) and the azimuthal quantum number (l).

- The principal quantum number (n) determines the energy level or shell of the electron. The higher the value of n, the farther the shell is from the nucleus.
- The azimuthal quantum number (l) determines the shape of the orbital. It can have values ranging from 0 to (n-1), representing different shapes such as s, p, d, and f orbitals.

The combination of these two quantum numbers determines the specific orbital and shell in which the electron resides.

**4. Conclusion:**
Therefore, the location of an element in the periodic table is determined by the quantum numbers, specifically the principal quantum number (n) and the azimuthal quantum number (l), which together determine the filled last orbital. The other quantum numbers, such as the magnetic quantum number (m) and the spin quantum number (s), provide more specific information about the orientation and spin state of the electron within the orbital.