What is the colour of the ash formed when a magnesium ribbon is burnt in the air?

Options

A. White
B. Black
C. Yellow
D. Pink

Answer

To determine the color of the ash formed when a magnesium ribbon is burnt in the air, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reaction**: When magnesium (Mg) is burned in the presence of air, it reacts with oxygen (O₂). The chemical reaction can be represented as:
\[ 2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO} \]

2. **Identifying the Product**: The product of this reaction is magnesium oxide (MgO).

3. **Characteristics of Magnesium Oxide**: Magnesium oxide is known to be a white solid. When magnesium burns, it produces this white powder as a result of the reaction.

4. **Conclusion**: The ash formed when magnesium ribbon is burnt in the air is therefore white in color.

### Final Answer:
The color of the ash formed when a magnesium ribbon is burnt in the air is **white**.

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