Give the correct order of initials T or F for following statements. Use T if statement is true and F if it is false :
Me-CH=C=C=CH-Br is optically active.
All optically active compound are chiral.
All chiral pyramndal molecules are optically inactive.
`{:(CH_(3)-CH_(2)-CH_(2)-COOH "and" CH_(3)-underset(COOH)underset(|)"CH"-CH_(3)` ),("are positional isomers."):}

Options

A. TTTF
B. FTFT
C. FTFF
D. TFTT

Explanation

To solve the question, we need to evaluate each statement one by one and determine whether they are true (T) or false (F).

### Statement Analysis:

1. **Statement 1**: "Me-CH=C=C=CH-Br is optically active."
- **Analysis**: The compound Me-CH=C=C=CH-Br has multiple double bonds and is symmetrical. For a compound to be optically active, it must lack a plane of symmetry and have chiral centers. Since this compound has symmetry, it is not optically active.
- **Conclusion**: **F** (False)

2. **Statement 2**: "All optically active compounds are chiral."
- **Analysis**: This statement is true. By definition, an optically active compound must be chiral, meaning it cannot be superimposed on its mirror image. Therefore, all optically active compounds are indeed chiral.
- **Conclusion**: **T** (True)

3. **Statement 3**: "All chiral pyramidal molecules are optically inactive."
- **Analysis**: This statement is false. Chiral pyramidal molecules can be optically active if they do not have a plane of symmetry. For example, ammonia (NH3) is a chiral molecule and is optically active due to its pyramidal shape.
- **Conclusion**: **F** (False)

4. **Statement 4**: "CH3-CH2-CH2-COOH and CH3-COOH-CH(CH3) are positional isomers."
- **Analysis**: Positional isomers differ in the position of a functional group or a double bond in the carbon chain. In this case, the two compounds have the same molecular formula but differ in the position of the carboxylic acid group. Thus, they are indeed positional isomers.
- **Conclusion**: **T** (True)

### Final Answers:
1. F
2. T
3. F
4. T

### Summary of Answers:
- Statement 1: F
- Statement 2: T
- Statement 3: F
- Statement 4: T