The number of electrons lost in the following change is
`Fe+H_(2)OrarrFe_(3)O_(4)+H_(2)`

Options

A. `2`
B. `4`
C. `6`
D. `8`

Explanation

To determine the number of electrons lost in the reaction:

\[ \text{Fe} + \text{H}_2\text{O} \rightarrow \text{Fe}_3\text{O}_4 + \text{H}_2 \]

we will follow these steps:

### Step 1: Identify the oxidation states of iron in the reactants and products.
- In the reactant, elemental iron (Fe) has an oxidation state of 0.
- In the product, Fe₃O₄, we need to calculate the oxidation state of iron.

### Step 2: Calculate the oxidation state of iron in Fe₃O₄.
- The formula for Fe₃O₄ can be expressed as:
\[ 3x + 4(-2) = 0 \]
where \( x \) is the oxidation state of iron.
- Solving for \( x \):
\[ 3x - 8 = 0 \implies 3x = 8 \implies x = \frac{8}{3} \]
- Therefore, the oxidation state of iron in Fe₃O₄ is \( \frac{8}{3} \).

### Step 3: Determine the change in oxidation state.
- The change in oxidation state for iron from 0 to \( \frac{8}{3} \) indicates that iron is losing electrons.
- The number of electrons lost per iron atom can be calculated as:
\[ \text{Electrons lost} = \text{Final oxidation state} - \text{Initial oxidation state} = \frac{8}{3} - 0 = \frac{8}{3} \]

### Step 4: Calculate the total number of electrons lost.
- Since there are 3 iron atoms in Fe₃O₄, the total number of electrons lost is:
\[ \text{Total electrons lost} = 3 \times \frac{8}{3} = 8 \]

### Conclusion:
The total number of electrons lost in the reaction is **8**.

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