The structural formula of the ore called natural magnet is

Options

A. `FeO_2`
B. `Fe_3O_4`
C. `FeO_3`
D. `Fe_2O_4`

Answer

To solve the question regarding the structural formula of the ore called natural magnet, we can follow these steps:

### Step 1: Identify the ores of iron
Natural magnet refers to a specific type of iron ore known for its magnetic properties. The two main ores of iron are hematite and magnetite.

### Step 2: Understand the properties of magnetite
Among these ores, magnetite is the one that exhibits natural magnetism. This is crucial because the question specifically asks for the ore known as the natural magnet.

### Step 3: Determine the chemical formula of magnetite
The chemical formula for magnetite is Fe3O4. This indicates that magnetite consists of three iron (Fe) atoms and four oxygen (O) atoms.

### Step 4: Evaluate the options given in the question
The options provided are:
1. FeO2
2. Fe3O4
3. FeO3
4. Fe2O4

From our knowledge, we can see that option 2, Fe3O4, matches the chemical formula for magnetite.

### Step 5: Conclude the answer
Thus, the structural formula of the ore called natural magnet is **Fe3O4**.

### Final Answer:
The structural formula of the ore called natural magnet is **Fe3O4** (option 2).

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