Which of the following statement is not applicable to `H_2SO_4` ?

Options

A. The molecules are associated by H - bonds
B. Oxidation state of S is +6
C. The hybrid state of S and O atoms of OH groups is same
D. The acid always exhibits a basicity of two

Answer

To determine which statement is not applicable to \( H_2SO_4 \), we will analyze each statement provided in the question.

### Step 1: Analyze the structure of \( H_2SO_4 \)
The molecular structure of sulfuric acid (\( H_2SO_4 \)) consists of a sulfur atom (S) bonded to four oxygen atoms (O), two of which are part of hydroxyl groups (–OH), and two are double-bonded to sulfur. The structure can be represented as follows:

\[ \text{O} \\ || \\ \text{S} - \text{O} - \text{H} \\ | \\ \text{O} - \text{H} \]

### Step 2: Evaluate the first statement: "The molecules are associated by H-bonds"
In liquid \( H_2SO_4 \), hydrogen bonds can form between the hydroxyl groups of different molecules. Therefore, this statement is applicable.

### Step 3: Evaluate the second statement: "The oxidation state of Sulfur is +6"
To find the oxidation state of sulfur in \( H_2SO_4 \), we can set up the equation based on the known oxidation states of hydrogen (+1) and oxygen (-2):

\[ 2(+1) + x + 4(-2) = 0 \\ 2 + x - 8 = 0 \\ x = +6 \]

Thus, the oxidation state of sulfur is indeed +6, making this statement applicable.

### Step 4: Evaluate the third statement: "The hybrid state of Sulfur and O atoms of OH groups are the same"
The hybridization of sulfur in \( H_2SO_4 \) is \( sp^3 \) because it has four regions of electron density (four bonds). The oxygen atoms in the hydroxyl groups also exhibit \( sp^3 \) hybridization due to their tetrahedral arrangement (one bond with sulfur and two with hydrogen, plus one lone pair). Therefore, this statement is applicable.

### Step 5: Evaluate the fourth statement: "The acid always exhibits Basicity of 2"
While \( H_2SO_4 \) can theoretically donate two protons (H+ ions), it does not always exhibit a basicity of 2 in every reaction. For instance, if \( H_2SO_4 \) reacts with a base that can only neutralize one proton, such as \( NaOH \), it will only donate one proton, leading to the formation of \( NaHSO_4 \) (an acidic salt). Thus, this statement is not universally applicable.

### Conclusion
The statement that is not applicable to \( H_2SO_4 \) is: **"The acid always exhibits Basicity of 2."**

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