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Date: 31-12-2019
1471
Date: 28-8-2018
1469
Date: 17-5-2017
2781
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Conjugated dienes are two double bonds separated by a single bond
Nonconjugated (Isolated) Dienes are two double bonds are separated by more than one single bond.
When using electrostatic potential maps, it is observed that the pi electron density overlap is closer together and delocalized in conjugated dienes, while in non conjugated dienes the pi electron density is located differently across the molecule. Since having more electron density delocalized makes the molecule more stable conjugated dienes are more stable than non conjugated
For example in 1,3-butadiene the carbons with the single bond are sp2 hybridized unlike in nonconjugated dienes where the carbons with single bonds are sp3 hybridized. This difference in hybridization shows that the conjugated dienes have more 's' character and draw in more of the pi electrons, thus making the single bond stronger and shorter than an ordinary alkane C-C bond (1.54Å).
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دراسة: عدم ترتيب الغرفة قد يدل على مشاكل نفسية
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علماء: تغير المناخ تسبب في ارتفاع الحرارة خلال موسم الحج
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العتبة العباسية تطلق المؤتمر العلمي لأسبوع الإمامة باللغة الإنجليزية
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