Q1P - Chemistry: Molecular Nature Of Matter And Change

Question

What type of central-atom orbital hybridization corresponds to each electron-group arrangement:

(a) trigonal planar

(b) octahedral

(c) linear

(d) tetrahedral

(e) trigonal bipyramidal?

Step-by-Step Solution

Answer

The Process of intermixing atomic orbitals to form a new atomic orbital is called hybridization. The new orbital formed is called a hybrid orbital.The total number of electrons in the new orbital is the same as the old ones.

Step1: For trigonal planar

When one s and two p orbitalsof the central atom mix together to give three hybrid orbitals or ${\mathbf{sp}}^{\mathbf{2}}$ hybrid orbitals.These hybrid orbitals point toward the vertices of an equilateral triangleand their axes are 120 degreesapart. 

Step2:For Octahedral

When one s, the threep, and two of dorbitals of the central atom mix and form six ${\mathbf{sp}}^{\mathbf{3}}{\mathbf{d}}^{\mathbf{2}}$ hybrid orbitals.These hybrid orbitals point to the vertices at an angle of 90 degrees of an octahedron.

Step3:For Linear

When one s and one p orbitalsof a central atom mix together gives rise to two sp hybrid orbitals These orbitals are oriented at 180 degreesto each other.

Step4:For Tetrahedral

When ones and all three p orbitalsof the central atom mix to give four ${\mathbf{sp}}^{\mathbf{3}}$ hybrid orbitals. These hybrid orbitals point toward the vertices of a tetrahedron at an angle109°28'.

Step5:For Trigonal bipyramidal

When one s, the three p, and one of the five d orbitalsof the central atom mix to give five ${\mathbf{sp}}^{\mathbf{3}}$  d hybrid orbitals These hybrid orbitals point to the vertices of a trigonal bipyramid.The equatorial orbitals are three hybrid orbitals that sit inside the horizontal plane and are inclined at 120 degrees to each other.

 

The remaining two orbitals, known as axial orbitals, are vertical at 90 degrees to the equatorial orbitals.