what is a Z alkene ?

Answer

To understand what a Z-alkene is, we can break down the explanation into a few clear steps:

### Step 1: Definition of Z-Alkene
A Z-alkene is a type of alkene where the two higher priority substituents (groups) attached to the carbon atoms of the double bond are located on the same side of the double bond.

### Step 2: Identifying Priority
To determine which groups are of higher priority, we use the Cahn-Ingold-Prelog priority rules. According to these rules, the priority is assigned based on the atomic number of the atoms directly attached to the double-bonded carbons. The group with the higher atomic number gets the higher priority.

### Step 3: Visual Representation
Consider a double bond between two carbon atoms (C=C). If we label the groups attached to these carbon atoms as A, B, C, and D:
- Let’s say carbon 1 has groups A and B attached, and carbon 2 has groups C and D attached.
- If A and B are the higher priority groups and are on the same side of the double bond, then the compound is classified as a Z-alkene.

### Step 4: Example
For example, if we have a compound where:
- Group A (higher priority) is on the left side of the double bond,
- Group B (higher priority) is also on the left side of the double bond,
- Groups C and D (lower priority) are on the opposite side,
Then this compound is a Z-alkene.

### Conclusion
In summary, a Z-alkene is characterized by having the two higher priority groups on the same side of the double bond.

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