Here's how to determine the number of half-filled orbitals in a chlorine atom:

1. Electron Configuration:

* Chlorine (Cl) has an atomic number of 17, meaning it has 17 electrons.

* Its electron configuration is: 1s² 2s² 2p⁶ 3s² 3p⁵

2. Identifying Half-Filled Orbitals:

* 3p Sublevel: The 3p sublevel has 3 orbitals (3px, 3py, 3pz). Each orbital can hold a maximum of 2 electrons.

* The 3p sublevel has 5 electrons. This means one orbital is completely filled (2 electrons), and the other two orbitals are half-filled (1 electron each).

3. Answer:

Therefore, there are two half-filled orbitals in a chlorine atom.