Q11.43CP - Chemistry: Molecular Nature Of Matter And Change

Question

Hydrazine, ${\mathbf{N}}_2{\mathbf{H}}_4$ , and carbon disulfide, ${\mathbf{CS}}_2$ , form a cyclic molecule (right). 

1. Draw Lewis structures for ${\mathbf{N}}_2{\mathbf{H}}_4$ and  ${\mathbf{CS}}_2$.
2. How do electron-group arrangement, molecular shape, and hybridization of N change when ${\mathbf{N}}_2{\mathbf{H}}_4$ reacts to form the product?
3. How do electron-group arrangement, molecular shape, and hybridization of C change when ${\mathbf{CS}}_2$ reacts to form the product?

Step-by-Step Solution

Answer

1. The Lewis structure of  ${\mathrm{N}}_2{\mathrm{H}}_4$  and ${\mathrm{CS}}_2$  is trigonal planar with a single bond and linear shape with a double bond.
2. The hybridization of  ${\mathrm{N}}_2{\mathrm{H}}_4$  is sp³ hybridized which molecular shape of trigonal planar.
3. The hybridization of  ${\mathrm{CS}}_2$  is sp hybridized which molecular shape of trigonal planar.

Step 1: Bonding

Bonding may be defined as the force of attraction between two or more atoms to form a compound. The molecule can have the same atom and a different atom.

Hybridization may be defined as mixing the atomic orbital to form a hybrid orbital before bonding with another atomic orbital having a similar atomic orbital.

Step 2: Lewis Structure

Lewis’s structure is the structure that used the atom’s valence electron to form a bond between them. The bonds are formed by the sharing of an electron called a covalent bond.

${\mathbf{N}}_2{\mathbf{H}}_4$ , a molecule containing N-atom and H-atom having 5 electrons and 1 electron in the valence shell requires 3 electrons and 1 require to fulfil octet and duplet.

${\mathbf{CS}}_2$ , a molecule containing C-atom and S-atom having 4 electrons and 6electrons in the valence shell requires 4electrons and 2 require to fulfil the octet.

Step 3: Hybridisation

The hybridization of  ${\mathbf{N}}_2{\mathbf{H}}_4$  is sp³ hybridized has one s-orbital and three p-orbital. The N-atom has 5 electrons in the p-orbital and H-atom has 1 electron in the s-orbital forming a sp³hybridized orbital after mixing.

The geometry of the molecule is tetrahedral but the shape of the molecule is trigonal planar having 3 single bonds and 1 lone pair.

The N-atom has 5 electrons in the valence shell forming a bond with 3 electrons and two electrons as lone pair.

Step 4: Hybridisation

The hybridization of  ${\mathbf{CS}}_2$ is sp hybridized having one s-orbital and three p-orbital. 

The C-atom has 4 electrons in the p-orbital and S-atom has 6 electrons in the p-orbital forming a sp hybridized orbital after mixing.

The geometry of the molecule is tetrahedral but the shape of the molecule is trigonal planar having 2 double bonds.

The C-atom have 4 electrons in the valence shell from a double bond and S-atom has 6 electrons from two double bond and lone pair.