Which intermolecular force is most responsible in allowing xenon gas to liquefy ?

Options

A. London forces
B. lon - dipole
C. Ionic
D. Dipole - dipole

Answer

To determine which intermolecular force is most responsible for allowing xenon gas to liquefy, we can follow these steps:

### Step 1: Understand the Nature of Xenon
Xenon is a noble gas with an atomic number of 54. Being a noble gas, it is non-polar in nature.

**Hint:** Remember that noble gases have complete electron shells, making them stable and non-polar.

### Step 2: Identify the Intermolecular Forces
In non-polar molecules like xenon, the primary intermolecular forces at play are London dispersion forces, which arise from the formation of instantaneous dipoles. These dipoles occur due to fluctuations in electron density.

**Hint:** Focus on how electron movement can create temporary dipoles in non-polar molecules.

### Step 3: Explain Instantaneous and Induced Dipoles
Instantaneous dipoles are formed when there is a temporary uneven distribution of electrons in a molecule. When these instantaneous dipoles come close to other non-polar molecules, they can induce dipoles in those molecules, leading to an attractive force known as London dispersion forces.

**Hint:** Think about how temporary changes in electron distribution can influence neighboring molecules.

### Step 4: Confirm the Type of Forces in Xenon
Since xenon is non-polar, the only significant intermolecular force it experiences is the London dispersion force. This force is crucial for the liquefaction of xenon gas, as it allows the molecules to come closer together under the right conditions (such as low temperature and high pressure).

**Hint:** Recall that London forces are the only type of intermolecular force present in non-polar substances.

### Step 5: Evaluate Other Intermolecular Forces
- **Ion-dipole forces**: These occur between ions and polar molecules, which do not apply to xenon.
- **Ionic forces**: These are between charged ions and are not relevant for noble gases.
- **Dipole-dipole forces**: These occur between polar molecules, which xenon is not.

**Hint:** Compare the characteristics of xenon with the definitions of other intermolecular forces to eliminate incorrect options.

### Conclusion
The intermolecular force most responsible for allowing xenon gas to liquefy is **London dispersion forces**.

**Final Answer:** London forces (Option 1) are the correct answer.