Which of the following does not contain Mg?

Options

A. Magnetite
B. Asbestos
C. Magnesite
D. Canalile

Answer

To determine which of the following options does not contain magnesium (Mg), we will analyze each option one by one:

1. **Magnetite**:
- Magnetite is a rock mineral and is one of the main ores of iron.
- Its chemical formula is Fe3O4, which consists of iron (Fe) and oxygen (O) only.
- Therefore, Magnetite does not contain magnesium.

2. **Asbestos**:
- Asbestos is a naturally occurring fibrous silicate mineral.
- Its formula is CaMg3SiO3·4H2O, which includes calcium (Ca), magnesium (Mg), silicon (Si), and water (H2O).
- Hence, Asbestos does contain magnesium.

3. **Magnesite**:
- Magnesite is a mineral that is primarily composed of magnesium carbonate.
- Its chemical composition is MgCO3, which clearly indicates the presence of magnesium.
- Therefore, Magnesite contains magnesium.

4. **Carnallite**:
- Carnallite is an evaporite mineral that is a hydrated potassium magnesium chloride.
- Its chemical formula is KMgCl3·6H2O, which includes potassium (K), magnesium (Mg), chlorine (Cl), and water (H2O).
- Thus, Carnallite contains magnesium.

After analyzing all the options, we conclude that:

**The correct answer is: Magnetite does not contain magnesium.**

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