Consider following properties of the noble gases.
I. They readily form compounds which are colourless.
II: They generally do not form ionic compounds.
III: Xenon has variable oxidation states in its compounds
IV : the smaller He and Ne do not form clathrate compounds.
Select correct properties.

Options

A. I,II,III
B. III,III,IV
C. I,III,IV
D. All

Answer

To solve the question regarding the properties of noble gases, let's analyze each statement step by step.

### Step 1: Analyze Statement I
**Statement I:** They readily form compounds which are colorless.

- **Analysis:** Noble gases are known for their stability due to having a complete octet. While xenon can form compounds, these compounds are not necessarily colorless. For example, some xenon compounds can exhibit color. Therefore, this statement is **not true**.

### Step 2: Analyze Statement II
**Statement II:** They generally do not form ionic compounds.

- **Analysis:** Noble gases, due to their stable electronic configuration, do not readily form ionic compounds. The compounds that xenon forms are primarily covalent in nature. Thus, this statement is **true**.

### Step 3: Analyze Statement III
**Statement III:** Xenon has variable oxidation states in its compounds.

- **Analysis:** Xenon is unique among noble gases as it can exhibit multiple oxidation states in its compounds, such as +2, +4, +6, etc. For instance, in compounds like XeOF4 and XeOF6, xenon shows variable oxidation states. Therefore, this statement is **true**.

### Step 4: Analyze Statement IV
**Statement IV:** The smaller He and Ne do not form clathrate compounds.

- **Analysis:** Helium (He) and Neon (Ne) are indeed too small and stable to form clathrate compounds, which are typically formed by larger noble gases. Hence, this statement is **true**.

### Conclusion
Based on the analysis of each statement:
- Statement I is **not true**.
- Statements II, III, and IV are **true**.

Thus, the correct properties of noble gases are **II, III, and IV**.

### Final Answer
The correct answer is option **B (2, 3, and 4)**.

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