Colour of Taj Mahal in Agra is changed due to

Options

A. sunlight
B. acid rain
C. slaked Iime
D. corrosion

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question:**
The question asks why the color of the Taj Mahal in Agra has changed over time.

2. **Identifying the Factors:**
The main factors that can affect the color of the Taj Mahal include environmental pollutants such as sulfur dioxide (SO₂) and nitrogen dioxide (NO₂), which are released from nearby factories.

3. **Role of Acid Rain:**
These pollutants can lead to the formation of acid rain. Acid rain is rain that has a lower pH than normal due to the presence of sulfuric acid (H₂SO₄) and nitric acid (HNO₃) formed from the reaction of these gases with water in the atmosphere.

4. **Chemical Reaction with Marble:**
The Taj Mahal is primarily made of white marble, which is composed of calcium carbonate (CaCO₃). When acid rain falls on the marble, a chemical reaction occurs:
\[ \text{CaCO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{CaSO}_4 + \text{H}_2\text{O} + \text{CO}_2 \]
This reaction produces calcium sulfate (CaSO₄), water (H₂O), and carbon dioxide (CO₂).

5. **Resulting Color Change:**
As a result of this reaction, the marble loses its original white color and can take on a yellowish hue due to the formation of calcium sulfate and the dissolution of the marble surface.

6. **Conclusion:**
Therefore, the change in color of the Taj Mahal is primarily due to acid rain, which reacts with the marble and alters its appearance.

**Final Answer:**
The color of the Taj Mahal in Agra has changed due to acid rain.

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