Which of the following compounds exhibits geometrical isomerism ?

Options

A. `C_2H_5Br`
B. `(CH)_2(COOH)_2`
C. `CH_3CHO`
D. `(CH_2)_2(COOH)_2`

Explanation

To determine which of the given compounds exhibits geometrical isomerism, we need to follow these steps:

### Step 1: Understand the conditions for geometrical isomerism
Geometrical isomerism occurs in compounds that have:
1. A double bond between carbon atoms (C=C).
2. Different groups attached to the carbon atoms involved in the double bond, allowing for cis (same side) and trans (opposite side) configurations.

### Step 2: Analyze the given compounds
Let's evaluate each option based on the conditions for geometrical isomerism.

1. **C2H5Br (Ethyl bromide)**:
- Structure: CH3-CH2-Br
- Analysis: There is no double bond between carbon atoms. Therefore, it cannot exhibit geometrical isomerism.

2. **C2H2 (Ethylene)**:
- Structure: H2C=CH2
- Analysis: This compound has a double bond between the two carbon atoms, but both carbon atoms have two hydrogen atoms attached. Thus, it does not meet the requirement for different groups on each carbon, and cannot exhibit geometrical isomerism.

3. **CH3CHO (Acetaldehyde)**:
- Structure: CH3-C(=O)H
- Analysis: This compound has a carbonyl group (C=O) but does not have a double bond between two carbon atoms. Therefore, it cannot exhibit geometrical isomerism.

4. **C2H4 (Ethylene)**:
- Structure: H2C=CH2
- Analysis: Similar to the previous analysis, this compound has a double bond but does not have different groups on the carbon atoms. Thus, it cannot exhibit geometrical isomerism.

### Conclusion
None of the provided options exhibit geometrical isomerism based on the analysis of their structures. However, if we had a compound like 2-butene (C4H8), which has the structure CH3-CH=CH-CH3, it would exhibit geometrical isomerism due to the presence of different groups on the carbon atoms involved in the double bond.

### Final Answer
None of the given compounds exhibit geometrical isomerism.

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