Which of the following has highest boiling point ?

Options

A. `C_(2)H_(5)OH`
B. `CH_(3)CO OH`
C. `CH_(3)COCH_(3)`
D. `HCO OCH_(3)`

Explanation

To determine which compound has the highest boiling point among the given options, we need to analyze the molecular structures and the presence of hydrogen bonding. Here’s a step-by-step solution:

### Step 1: Identify the Compounds
Assuming the compounds provided have the same molecular formula (C3H6O2), we will analyze their structures. The compounds can be represented as:
1. CH3-CH2-COOH (Propanoic acid)
2. CH3-COOH (Acetic acid)
3. CH3-CH=CH2 (Propene)
4. CH3-CHO (Acetaldehyde)

### Step 2: Analyze Molecular Weights
All compounds have the same molecular weight (46 g/mol), which does not help in determining the boiling point directly. Therefore, we need to look at the types of intermolecular forces present.

### Step 3: Identify Intermolecular Forces
The boiling point of a substance is influenced by the strength of its intermolecular forces. The primary forces to consider here are:
- Hydrogen bonding
- Dipole-dipole interactions
- Van der Waals forces

### Step 4: Check for Hydrogen Bonding
Hydrogen bonding occurs when hydrogen is bonded to highly electronegative atoms like oxygen or nitrogen. We will check each compound for the presence of hydrogen bonds:
1. **Propanoic acid (CH3-CH2-COOH)**: Contains -OH group, can form hydrogen bonds.
2. **Acetic acid (CH3-COOH)**: Contains -OH group, can form hydrogen bonds.
3. **Propene (CH3-CH=CH2)**: Does not have -OH group, cannot form hydrogen bonds.
4. **Acetaldehyde (CH3-CHO)**: Contains -OH group, can form hydrogen bonds.

### Step 5: Compare the Number of Hydrogen Bonds
- **Propanoic acid**: Can form multiple hydrogen bonds due to its -COOH group.
- **Acetic acid**: Can form hydrogen bonds but less than propanoic acid.
- **Propene**: No hydrogen bonding.
- **Acetaldehyde**: Can form hydrogen bonds, but fewer than propanoic acid.

### Step 6: Conclusion
Since propanoic acid can form more hydrogen bonds compared to the other compounds, it will have the highest boiling point. Therefore, the compound with the highest boiling point is **Propanoic acid (CH3-CH2-COOH)**.

### Final Answer
**Propanoic acid (CH3-CH2-COOH) has the highest boiling point.**