Silver, gold and platinum are called noble metals because __________.

Options

A. these are costly
B. these are precious
C. these have very less reactivity
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Noble Metals:** Noble metals are a group of metals that are known for their resistance to corrosion and oxidation in moist air. They are typically less reactive than other metals.

2. **Identifying Noble Metals:** The metals in question are Silver (Ag), Gold (Au), and Platinum (Pt). These metals are categorized as noble metals due to their unique properties.

3. **Reactivity Series:** In the reactivity series of metals, noble metals are found at the bottom, indicating that they are among the least reactive metals. This means they do not easily react with other elements or compounds.

4. **Reason for the Name:** The term "noble" is used because these metals do not tarnish or corrode easily, which is similar to the behavior of noble gases that are also unreactive.

5. **Conclusion:** Therefore, Silver, Gold, and Platinum are called noble metals because they have very low reactivity and do not react with air, water, or most chemicals.

**Final Answer:** Silver, gold, and platinum are called noble metals because they have very low reactivity.

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