Which compound is formed when iron reacts with carbon?

Options

A. `FeC_2`
B. `Fe_3C`
C. `FeC_3`
D. `Fe_2C`

Answer

To solve the question of which compound is formed when iron reacts with carbon, we can follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are iron (Fe) and carbon (C).

### Step 2: Determine the Product
When iron reacts with carbon, they combine to form a compound known as cementite. The chemical formula for cementite is Fe₃C.

### Step 3: Write the Reaction
The balanced chemical equation for the reaction can be represented as:
\[ 3 \text{Fe} + \text{C} \rightarrow \text{Fe}_3\text{C} \]
This indicates that three atoms of iron react with one atom of carbon to form one molecule of cementite.

### Step 4: Analyze the Properties
Cementite (Fe₃C) is known to be a hard and brittle material, which is significant in metallurgy and materials science.

### Step 5: Select the Correct Option
Given the options in the question, we can conclude that the correct answer is the compound cementite, represented by the formula Fe₃C.

### Final Answer
The compound formed when iron reacts with carbon is **Fe₃C (cementite)**.

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