When magnesium ribbon burnt, it produces :

Options

A. magnesium hydroxide
B. magnesium oxide
C. magnesium chloride
D. magnesium sulphate

Explanation

**Step-by-Step Solution:**

1. **Understanding the Reaction**: When magnesium (Mg) is burned, it reacts with oxygen (O2) present in the air. This is a combustion reaction.

2. **Identifying the Products**: The main product formed when magnesium burns in the presence of oxygen is magnesium oxide (MgO).

3. **Chemical Equation**: The balanced chemical equation for the reaction can be represented as:
\[ 2Mg + O_2 \rightarrow 2MgO \]
This shows that two moles of magnesium react with one mole of oxygen to produce two moles of magnesium oxide.

4. **Properties of the Product**: Magnesium oxide is a white powder or ash that is formed after the combustion of magnesium.

5. **Conclusion**: Therefore, when magnesium ribbon is burnt, it produces magnesium oxide (MgO).

**Final Answer**: When magnesium ribbon is burnt, it produces magnesium oxide (MgO).

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