Valence Bond Theory
Chapter Name : Chemical Bonding And Molecular Structure |
Sub Topic Code : 102_11_04_06_04 |
Topic Name : Valence Bond Theory |
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Sub Topic Name : Overlapping Of Atomic Orbitals |
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Introduction
• When orbitals of two atoms come close to form bond, their overlap may be positive, negative or zero depending upon the sign (phase) and direction of orientation of amplitude of orbital wave function in space. • Orbitals forming bond should have same sign (phase) and orientation in space. This is called positive overlap. • Overlap with opposite sign (phase) and orientation in space is called negative overlap.
Pre-Requisites:
Covalent bond, molecule , orbital
Activity:
Overlapping orbitals are like tomato slices kept in such a way that they overlap.
Real Life Question:
How do complex polyatomic molecules form?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Covalent bond | Covalent bond forms when there is sharing of electrons between two atoms. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Ball, dumbbell | A ball and a dumb bell are like the s and p orbitals of atoms. |
Real life uses :
• The geometry of the molecules is also important apart from the overlapping of orbitals for bond formation.
Places to visit :
Kitchen, gym, playground
Practical examples around us
| Examples | Explainations |
|---|---|
| Dumbbell, slices of tomato | Dumbbell is like the shape of a p orbital and like slices of tomato kept over each other, orbitals overlap in the same way making a bond. |
What you learn in Theory:
Different type of overlapping takes place depending on the phases of orbitals (negative, positive and zero).
What you learn in Practice:
Overlapping of atomic orbitals helps to form many molecules such as water.