A double bond is a bond between two elements that requires 2 pairs of elections rather than 1. It is shorter and stronger than a single bond. The most common double bond appears between two carbon atoms.
Since the the two atoms are connected by two bonds, it makes them incapable of rotating.
Double bonds are stronger than single bonds because there are two bonds instead of one. They are also shorter because the bonds bend a bit but single bonds stay straight. Since there are two bonds connecting two atoms, they cannot rotate.
When two atoms with three sp2 orbitals approach each other, two of their sp2 orbitals overlap, forming a sigma bond. On the other hand, their two p-orbitals form a pi bond. Since they want to be overlapped to the maximum, the sp2 orbitals stay parralell to each other. Therefore, the two atoms connected by a double bond cannot rotate.
1. Why can't atoms connected by a double bond rotate?
2. Why is a double bond shorter than a single bond?
3. Why are double bonds stronger than single bonds?
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