Arc welding of metals can be done normally using 

Options

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

Answer

To solve the question regarding which noble gas is typically used in arc welding of metals, let's break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Process**: Arc welding is a process that uses an electric arc to melt and join metals. It requires a protective atmosphere to prevent oxidation and contamination of the weld.

2. **Role of Noble Gases**: Noble gases are often used in welding because they are inert and do not react with other elements. This property helps in creating a protective environment around the weld.

3. **Identifying the Options**: The options provided are:
- Neon
- Argon
- Krypton
- Xenon

4. **Evaluating Each Option**:
- **Neon**: While it is a noble gas, it is not commonly used in welding due to its low density and lower effectiveness in shielding.
- **Argon**: This is the most commonly used noble gas in arc welding. It provides an effective inert atmosphere that protects the weld from oxidation.
- **Krypton**: Similar to neon, it is not typically used in welding applications.
- **Xenon**: While it is a noble gas, it is not practical for welding due to its high cost and lower availability.

5. **Conclusion**: Based on the evaluation, **Argon** is the correct answer as it is the noble gas that is commonly used in arc welding of metals.

### Final Answer:
Arc welding of metals can be done normally using **Argon**.

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