lewis diagram cs2 refers to the Lewis structure of carbon disulfide, \(\mathrm{CS_2}\), showing the placement of valence electrons as bonding pairs and lone pairs. The chemically preferred drawing satisfies octets on all atoms with minimal formal charge.
Valence-electron accounting
Carbon contributes 4 valence electrons and each sulfur contributes 6, giving a total of 16 valence electrons available for bonds and lone pairs.
| Element | Valence electrons per atom | Number of atoms | Total contribution |
|---|---|---|---|
| C | \(4\) | \(1\) | \(4\) |
| S | \(6\) | \(2\) | \(12\) |
| Total | \(16\) |
Bonding pattern and octets
Carbon is the central atom in \(\mathrm{CS_2}\) because it forms the backbone of the molecule with two terminal sulfurs. Two double bonds, one to each sulfur, complete the octet on carbon and on both sulfur atoms. Each sulfur carries two lone pairs; carbon carries no lone pairs in the lowest-formal-charge structure.
Preferred Lewis structure
\(\mathrm{S{=}C{=}S}\) with two lone pairs on each S, no lone pairs on C, and all formal charges equal to zero.
Formal-charge confirmation
Formal charge is computed as
Here \(V\) is the number of valence electrons for the free atom, \(N\) is the number of nonbonding (lone-pair) electrons on that atom in the Lewis structure, and \(B\) is the number of bonding electrons shared in bonds to that atom.
| Atom in \(\mathrm{S{=}C{=}S}\) | \(V\) | \(N\) | \(B\) | \(\mathrm{FC} = V - (N + B/2)\) |
|---|---|---|---|---|
| C (central) | \(4\) | \(0\) | \(8\) | \(4 - (0 + 8/2) = 0\) |
| S (each terminal) | \(6\) | \(4\) | \(4\) | \(6 - (4 + 4/2) = 0\) |
Molecular geometry implied by the Lewis structure
Carbon has two electron-density regions (two \(\sigma\)-bond domains, one in each \(\mathrm{C{=}S}\) double bond) and no lone pairs. VSEPR therefore predicts a linear arrangement around carbon with a bond angle of approximately \(180^\circ\). The symmetry of \(\mathrm{S{=}C{=}S}\) cancels bond dipoles, giving a nonpolar molecule despite polar \(\mathrm{C{-}S}\) bonds.
Visualization of the Lewis diagram for CS2
Resonance and alternative drawings
Alternative connectivity patterns with unequal bond orders (for example, one \(\mathrm{C{\equiv}S}\) and one \(\mathrm{C{-}S}\)) introduce nonzero formal charges. The symmetric \(\mathrm{S{=}C{=}S}\) structure maintains octets with formal charges of zero on all atoms and represents the dominant Lewis description in general chemistry.