To draw the Lewis structure for CHCl3, also known as chloroform, we need to follow a series of steps that involve calculating the total valence electrons, drawing the skeletal structure, and then distributing the electrons to satisfy the octet rule for each atom.
Calculate the Total Valence Electrons:
- Carbon © has 4 valence electrons.
- Hydrogen (H) has 1 valence electron.
- Chlorine (Cl) has 7 valence electrons. Since there are three chlorine atoms, we multiply the valence electrons of one chlorine atom by 3.
- Total valence electrons = 4 © + 1 (H) + 7*3 (Cl) = 4 + 1 + 21 = 26 valence electrons.
Draw the Skeletal Structure:
- Carbon is the least electronegative atom and can form the most bonds, so it’s usually the central atom in organic compounds.
- Hydrogen can form only one bond, so it will be attached to the carbon.
- Chlorine atoms will also be attached to the carbon since carbon can form four bonds (to satisfy its octet), and we have three chlorine atoms and one hydrogen atom.
Distribute the Electrons:
- Start by connecting the atoms with single bonds. This uses 8 electrons (2 electrons for each of the 4 bonds: C-H and C-Cl for each of the three chlorines).
- Remaining electrons = 26 - 8 = 18 electrons.
- Distribute the remaining electrons to the atoms so that each atom achieves a noble gas electron configuration, satisfying the octet rule. Carbon already has 4 bonds (thus 8 electrons), and hydrogen has 2 electrons in a single bond with carbon, satisfying its duet.
- Each chlorine atom needs 8 electrons to satisfy its octet. With one single bond to carbon (2 electrons), each chlorine needs 6 more electrons, which are provided as 3 lone pairs.
Finalize the Structure:
- Carbon © is in the center, bonded to one hydrogen (H) and three chlorine (Cl) atoms.
- Hydrogen has 2 electrons (satisfying its duet).
- Carbon has 4 bonds (8 electrons), satisfying its octet.
- Each chlorine atom has one bond (2 electrons) and three lone pairs (6 electrons), satisfying its octet.
This results in the Lewis structure for CHCl3 (chloroform) where carbon is central, bonded to hydrogen and three chlorines, with the chlorines each having three lone pairs of electrons.
HTML Representation:
To visualize the structure, consider the following layout:
- Carbon © at the center.
- Hydrogen (H) bonded to carbon.
- Three chlorines (Cl) each bonded to carbon with three lone pairs of electrons.
This setup satisfies the octet rule for all atoms involved, ensuring a stable molecular configuration for chloroform (CHCl3).
Key Points: - Chloroform is a compound with one carbon, one hydrogen, and three chlorine atoms. - Its Lewis structure shows carbon at the center, bonded to hydrogen and the three chlorine atoms, with the chlorines each having three lone pairs of electrons. - This structure illustrates the molecule’s electron configuration, where each atom achieves a stable noble gas configuration, adhering to the octet rule for carbon, chlorine, and the duet rule for hydrogen.
