The oxidation number of phosphorous in `Mg_(2)P_2O_(7)` is

Options

A. `+5`
B. `-5`
C. `+6`
D. `-7`

Explanation

To find the oxidation number of phosphorus in the compound \( \text{Mg}_2\text{P}_2\text{O}_7 \), we can follow these steps:

### Step 1: Identify the oxidation states of known elements
In the compound \( \text{Mg}_2\text{P}_2\text{O}_7 \):
- Magnesium (Mg) typically has an oxidation state of +2.
- Oxygen (O) typically has an oxidation state of -2.

### Step 2: Set up the equation for the oxidation states
Let the oxidation state of phosphorus (P) be \( x \). Since there are 2 phosphorus atoms in the compound, their total contribution will be \( 2x \).

The total oxidation state can be expressed as:
\[ \text{Total oxidation state} = (\text{oxidation state of Mg}) + (\text{oxidation state of P}) + (\text{oxidation state of O}) \]

Substituting the known values:
\[ 2(\text{oxidation state of Mg}) + 2(\text{oxidation state of P}) + 7(\text{oxidation state of O}) = 0 \]
\[ 2(+2) + 2x + 7(-2) = 0 \]

### Step 3: Simplify the equation
Now, simplifying the equation:
\[ 4 + 2x - 14 = 0 \]
\[ 2x - 10 = 0 \]

### Step 4: Solve for \( x \)
Now, we can solve for \( x \):
\[ 2x = 10 \]
\[ x = 5 \]

### Conclusion
The oxidation number of phosphorus in \( \text{Mg}_2\text{P}_2\text{O}_7 \) is \( +5 \).

### Final Answer
The oxidation number of phosphorus in \( \text{Mg}_2\text{P}_2\text{O}_7 \) is \( +5 \).

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