Which among the following is not noble gas?

Options

A. Br
B. Kr
C. Ne
D. Xe

Answer

To determine which among the given options is not a noble gas, we can follow these steps:

### Step 1: Identify the Noble Gases
Noble gases are a group of elements found in Group 18 of the periodic table. The noble gases include:
- Helium (He)
- Neon (Ne)
- Argon (Ar)
- Krypton (Kr)
- Xenon (Xe)
- Radon (Rn)

### Step 2: Analyze the Given Options
The options provided are:
1. Bromine (Br)
2. Krypton (Kr)
3. Neon (Ne)
4. Xenon (Xe)

### Step 3: Classify Each Option
- **Bromine (Br)**: This element is found in Group 17 of the periodic table and is classified as a halogen, not a noble gas.
- **Krypton (Kr)**: This element is found in Group 18 and is a noble gas.
- **Neon (Ne)**: This element is also found in Group 18 and is a noble gas.
- **Xenon (Xe)**: This element is found in Group 18 and is a noble gas.

### Step 4: Conclusion
Among the options, the only element that is not a noble gas is **Bromine (Br)**.

### Final Answer
The element that is not a noble gas is **Bromine (Br)**.

---