Gold metal is affected by

Options

A. chlorine gas
B. oxygen gas
C. sulphur dioxide gas
D. helium gas

Answer

**Step-by-Step Solution:**

1. **Understanding Gold's Reactivity:** Gold is a noble metal, which means it is generally resistant to corrosion and oxidation. However, it can react under certain conditions.

2. **Identifying the Gas:** The question asks about which gas affects gold metal. From the video transcript, we learn that chlorine gas is the gas that can affect gold.

3. **Extraction Process:** The extraction of gold from its ores involves the use of chlorine gas. This process is known as chlorination. When chlorine gas is introduced to gold, it can react with it.

4. **Temperature Requirement:** The video mentions that this reaction occurs at a temperature of around 180 degrees Celsius. At this temperature, the chlorine gas can effectively react with the gold.

5. **Conclusion:** Therefore, the gas that affects gold metal is chlorine gas, especially when used in the extraction process at elevated temperatures.

**Final Answer:** Gold metal is affected by chlorine gas.

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