double bond

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inaccensa

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I'm really getting confused with the stability of single, double and triple

So the triple bond is stronger than double bond which in turn is stronger than a single bond. But overall, is an alkyne stronger than alkene. I keep thinking that during a reaction, a double or triple bond will easilt undergo electrophilic addition. Alkanes simply undergo combustion and free radical halogenation. It requires rigorous conditions. I understand that alkanes are more stable. Please someone verify this.

Q- Why are double bonds in benzene longer and weaker than alkenes? I know beneze is not on the list, but I want to understand this concept.

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The sigma bond is the strongest bond. Pi bonds are weaker than sigma bonds. Double and triple bonds are stronger than single bonds because they contain a sigma + pi and sigma + pi + pi bonds respectively compared to just the sigma bond of an alkane.

The double bonds in benzene are longer and weaker than in a linear alkene because benzene has aromaticity. Since the double bonds can move around in the ring, there are no set carbons that are the only ones that have double bonds; the pi electrons are shared throughout the ring. What this means is that rather than certain carbon-carbon bonds have double bond character, all the bonds have a partial double bond character. This partial double bond character is weaker than an actual double bond seen in linear alkenes. Since weaker bonds = longer bonds, the partial double bonds of benzene are longer than actual double bonds.

Hope this helps.
 
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