aansi jomi
Last Activity: 14 Years ago
E means entgegen(opposite) and Z means zusammen(together)...these are german words assigned to distinguish alkenes based on priority of substituents on both sides of the double bonds......priority is again based on atomic numbers.....e.g.
E Z
1 indicates high priority and 2 indicates low priority.....so the first molecule clearly shows that the priorities are directed opposite to each other hence assigned as E....and likewise Z for the second molecule.....(the priority is that carbon has higher atomic number than hydrogen)
important:
Isotopes: H vs D ? Since isotopes have identical atomic numbers, the mass number is used to discriminate them so D > H