What is the dominant intermolecular forces or bond that must be overcome in converting liquid `CH_(3)OH` to gas ?

Options

A. (a) London dispersion force
B. (b) Hydrogen bonding
C. (c) Dipole-dipole interaction
D. (d) Covalent bonds

Explanation

To determine the dominant intermolecular forces that must be overcome to convert liquid CH₃OH (methanol) to gas, we can follow these steps:

### Step 1: Identify the Intermolecular Forces in CH₃OH
- CH₃OH is a polar molecule due to the presence of the hydroxyl (-OH) group. The oxygen atom is more electronegative than hydrogen, leading to a dipole moment.

**Hint:** Look for the functional groups in the molecule that contribute to its polarity.

### Step 2: Determine the Type of Intermolecular Forces Present
- The primary intermolecular force in CH₃OH is hydrogen bonding. This occurs because hydrogen is bonded to an electronegative atom (oxygen), which allows it to interact with the lone pairs of electrons on oxygen atoms of neighboring CH₃OH molecules.

**Hint:** Recall that hydrogen bonding occurs when hydrogen is directly bonded to electronegative atoms like oxygen, nitrogen, or fluorine.

### Step 3: Understand the Process of Vaporization
- When converting liquid CH₃OH to gas, you need to overcome the intermolecular forces that hold the molecules together in the liquid state. In this case, it is the hydrogen bonds between the CH₃OH molecules.

**Hint:** Think about what happens at the molecular level when a liquid turns into a gas—molecules must gain enough energy to break free from their neighbors.

### Step 4: Evaluate Other Intermolecular Forces
- Other forces such as London dispersion forces and dipole-dipole interactions are present in all molecules but are not the dominant forces in CH₃OH. Covalent bonds are intramolecular forces and do not need to be overcome for vaporization.

**Hint:** Consider the strength and nature of the different types of intermolecular forces when determining which one is dominant.

### Conclusion
- The dominant intermolecular force that must be overcome in converting liquid CH₃OH to gas is **hydrogen bonding**.

**Final Answer:** Hydrogen bonding.