`Fe_(0.94) O to Fe^(3+)`, the equivalent mass of `Fe_(0.94)O` will be:

Options

A. `("mol. Mass")/(2)`
B. `("mol.mass")/(3)`
C. `(3xx " mol. Mass)/(8)`
D. `("mol.mass")/(0.87)`

Answer

To find the equivalent mass of Fe₀.94O when it is converted to Fe³⁺, we need to follow these steps:

### Step 1: Determine the oxidation state of iron in Fe₀.94O
In the compound Fe₀.94O, we know that the oxidation state of oxygen (O) is -2. Let the oxidation state of iron (Fe) be x. Since the compound is neutral, we can set up the following equation:

\[ 0.94x + (-2) = 0 \]

### Step 2: Solve for the oxidation state of iron
Rearranging the equation gives us:

\[ 0.94x = 2 \]

Now, solving for x:

\[ x = \frac{2}{0.94} \approx 2.127 \]

### Step 3: Calculate the change in oxidation state
The change in oxidation state when Fe goes from 2.127 to 3 can be calculated as:

\[ \text{Change in oxidation state} = 3 - 2.127 = 0.873 \]

### Step 4: Determine the molar mass of Fe₀.94O
To find the molar mass of Fe₀.94O, we need to calculate the contributions from iron and oxygen:

- Molar mass of Fe = 55.85 g/mol
- Molar mass of O = 16.00 g/mol

Calculating the molar mass:

\[ \text{Molar mass of Fe}_{0.94}\text{O} = (0.94 \times 55.85) + (1 \times 16.00) \]
\[ = 52.5 + 16.00 = 68.5 \text{ g/mol} \]

### Step 5: Calculate the equivalent mass
The equivalent mass is given by the formula:

\[ \text{Equivalent mass} = \frac{\text{Molar mass}}{n} \]

Where n is the change in oxidation state, which we found to be 0.873. Thus, we can calculate the equivalent mass:

\[ \text{Equivalent mass} = \frac{68.5}{0.873} \approx 78.5 \text{ g/equiv} \]

### Final Answer
The equivalent mass of Fe₀.94O when converted to Fe³⁺ is approximately **78.5 g/equiv**.

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