Which of the following is most polarised among noble gases ?

Options

A. Kr
B. He
C. Ar
D. Xe

Answer

To determine which noble gas is the most polarized among Krypton, Helium, Argon, and Xenon, we can follow these steps:

### Step 1: Understand Polarization
Polarization refers to the distortion of the electron cloud of an atom or molecule in the presence of an external electric field. The ability of an atom to be polarized depends on the number of electrons and the size of the electron cloud.

### Step 2: Identify the Noble Gases
The noble gases in the question are:
- Helium (He)
- Argon (Ar)
- Krypton (Kr)
- Xenon (Xe)

### Step 3: Determine the Atomic Numbers
Next, we need to find the atomic numbers of each noble gas:
- Helium (He) has an atomic number of 2.
- Argon (Ar) has an atomic number of 18.
- Krypton (Kr) has an atomic number of 36.
- Xenon (Xe) has an atomic number of 54.

### Step 4: Analyze the Relationship Between Atomic Number and Polarization
The polarization of noble gases increases with the number of electrons. This is because a larger number of electrons means a larger electron cloud, which can be more easily distorted. Therefore, the noble gas with the highest atomic number will be the most polarized.

### Step 5: Compare the Atomic Numbers
Among the noble gases listed:
- Helium (2) < Argon (18) < Krypton (36) < Xenon (54)

### Step 6: Conclusion
Since Xenon has the highest atomic number (54), it has the most electrons and thus is the most polarized noble gas among the options provided.

### Final Answer
**Xenon (Xe) is the most polarized noble gas.**

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