In which of the following the oxidation number of the underlined atom is maximum ?

Options

A. `H_4ulP_2O_7`
B. `KulAl(SO_4)_(2).12H_2O`
C. `K_2ul(Mn)O_4`
D. `Na_2ulSO_3`

Answer

To determine which of the given compounds has the maximum oxidation number for the underlined atom, we will calculate the oxidation states of the relevant atoms in each compound step by step.

### Step 1: Calculate the oxidation state in H4P2O7
1. **Identify the oxidation states**:
- Hydrogen (H) = +1
- Oxygen (O) = -2
- Let the oxidation state of Phosphorus (P) = x.

2. **Set up the equation**:
\[ 4(+1) + 2x + 7(-2) = 0 \]
Simplifying this gives:
\[ 4 + 2x - 14 = 0 \implies 2x - 10 = 0 \implies 2x = 10 \implies x = 5 \]

### Step 2: Calculate the oxidation state in KAl(SO4)2
1. **Identify the oxidation states**:
- Potassium (K) = +1
- Sulfate (SO4) = -2 (for each sulfate)
- Let the oxidation state of Aluminum (Al) = x.

2. **Set up the equation**:
\[ 2(+1) + x + 2(-2) = 0 \]
Simplifying this gives:
\[ 2 + x - 4 = 0 \implies x - 2 = 0 \implies x = 3 \]

### Step 3: Calculate the oxidation state in K2MnO4
1. **Identify the oxidation states**:
- Potassium (K) = +1
- Oxygen (O) = -2
- Let the oxidation state of Manganese (Mn) = x.

2. **Set up the equation**:
\[ 2(+1) + x + 4(-2) = 0 \]
Simplifying this gives:
\[ 2 + x - 8 = 0 \implies x - 6 = 0 \implies x = 6 \]

### Step 4: Calculate the oxidation state in Na2SO3
1. **Identify the oxidation states**:
- Sodium (Na) = +1
- Oxygen (O) = -2
- Let the oxidation state of Sulfur (S) = x.

2. **Set up the equation**:
\[ 2(+1) + x + 3(-2) = 0 \]
Simplifying this gives:
\[ 2 + x - 6 = 0 \implies x - 4 = 0 \implies x = 4 \]

### Summary of Oxidation States
- H4P2O7: P = +5
- KAl(SO4)2: Al = +3
- K2MnO4: Mn = +6
- Na2SO3: S = +4

### Conclusion
The maximum oxidation number among the calculated values is **+6**, which corresponds to Manganese in **K2MnO4**.

### Final Answer
**K2MnO4** has the maximum oxidation number of the underlined atom.

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