Which of the following statements `is//are` correct?

Options

A. `R-overset(O)overset(||)(C )-O-overset(O)overset(||)(C )-R` is an unsaturated compound.
B. Neohydrocarbons contain a `3^(@)C` atom.
C. The `IUPAC` name of isopropyl alcohol is propan-2-ol.
D. The `IUPAC` name of `(CH_(3) CN)` ie ethanenitrile.

Explanation

To determine which of the statements are correct, we will analyze each statement one by one.

### Step 1: Analyze the First Statement
- The first statement describes a structure that is claimed to be a saturated compound.
- A saturated compound contains only single bonds between carbon atoms (C-C), while an unsaturated compound contains at least one double (C=C) or triple bond (C≡C).
- The given structure has C single bond C, indicating it is indeed a saturated compound.
- However, the statement claims it is unsaturated, which is incorrect.

**Conclusion**: The first statement is **incorrect**.

### Step 2: Analyze the Second Statement
- The second statement claims that neohydrocarbons contain a tertiary carbon atom.
- Neohydrocarbons are characterized by having a carbon atom that is bonded to three other carbon atoms (making it tertiary).
- However, the examples provided, such as neopentane and neohexane, show that they actually contain quaternary carbon atoms (bonded to four other carbon atoms).
- Therefore, the statement is incorrect.

**Conclusion**: The second statement is **incorrect**.

### Step 3: Analyze the Third Statement
- The third statement claims that the IUPAC name of isopropyl alcohol is propane-2-ol.
- Isopropyl alcohol has the structure where the hydroxyl group (-OH) is attached to the second carbon of a three-carbon chain.
- The correct IUPAC naming for this compound is indeed propane-2-ol.

**Conclusion**: The third statement is **correct**.

### Step 4: Analyze the Fourth Statement
- The fourth statement claims that the IUPAC name of CH3CN is ethane nitrile.
- CH3CN contains a nitrile group (C≡N) and two carbon atoms.
- The correct IUPAC name for CH3CN is indeed ethane nitrile, and it is also known as acetonitrile.

**Conclusion**: The fourth statement is **correct**.

### Final Conclusion
- The correct statements are the **third** and **fourth** statements.

### Summary of Correct Statements
- **Correct Statements**: 3 and 4
- **Incorrect Statements**: 1 and 2

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