Which structure shows the correct electron arrangement in CCl4?
The Correct Answer and Explanation is:
In carbon tetrachloride (CCl₄), the carbon atom is at the center, bonded to four chlorine atoms. The correct electron arrangement involves the sharing of electrons between the carbon atom and each chlorine atom. Here’s a step-by-step breakdown:
- Electron Configuration of Carbon: The atomic number of carbon is 6. Its electron configuration is 1s² 2s² 2p², meaning it has four electrons in its outermost shell (the second energy level). Carbon needs four more electrons to complete its octet, which it achieves by bonding with four chlorine atoms.
- Electron Configuration of Chlorine: The atomic number of chlorine is 17, and its electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁵. Chlorine has seven valence electrons and needs one more electron to achieve a stable octet.
- Bond Formation: In CCl₄, each chlorine atom shares one electron with the carbon atom, forming a covalent bond. This results in carbon sharing one electron with each chlorine, completing its octet. Each chlorine atom also shares one electron with carbon, filling its own octet.
- Electron Arrangement in CCl₄:
- The carbon atom at the center of CCl₄ has a full octet, consisting of eight electrons in its valence shell: four electrons from its own, and four electrons shared from the chlorine atoms.
- Each chlorine atom has a complete octet with seven of its own electrons and one shared with carbon.
The molecular geometry of CCl₄ is tetrahedral, with the chlorine atoms arranged symmetrically around the central carbon atom. The electron pairs around the central carbon atom also follow the VSEPR theory (Valence Shell Electron Pair Repulsion), where the pairs of electrons arrange themselves as far apart as possible to minimize repulsion, leading to the tetrahedral structure.
Thus, the electron arrangement in CCl₄ shows that carbon is bonded to four chlorine atoms with single bonds, and each atom achieves a stable octet through electron sharing.
