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 one by one.

### Step 1: Analyze the first statement
**Statement:** The molecules are associated with hydrogen bonds.
**Analysis:** This statement is correct. \( H_2SO_4 \) can form hydrogen bonds due to the presence of hydroxyl (OH) groups. Each \( H_2SO_4 \) molecule can form hydrogen bonds with other \( H_2SO_4 \) molecules.

### Step 2: Analyze the second statement
**Statement:** The oxidation state of sulfur is +6.
**Analysis:** This statement is also correct. To find the oxidation state of sulfur in \( H_2SO_4 \):
- Let the oxidation state of sulfur be \( x \).
- The equation based on the compound's neutrality is:
\[ 2(+1) + x + 4(-2) = 0 \]
Simplifying gives:
\[ 2 + x - 8 = 0 \implies x = +6 \]
Thus, the oxidation state of sulfur is indeed +6.

### Step 3: Analyze the third statement
**Statement:** The hybrid state of sulfur and the oxygen atoms in the OH groups is the same.
**Analysis:** This statement is correct. The hybridization of sulfur in \( H_2SO_4 \) is \( sp^3 \) because it has 4 sigma bonds (from 4 bonds). The oxygen in the hydroxyl groups also has a steric number of 4 (2 lone pairs and 2 sigma bonds), leading to \( sp^3 \) hybridization as well. Therefore, they have the same hybrid state.

### Step 4: Analyze the fourth statement
**Statement:** Acid always shows a basicity of 2.
**Analysis:** This statement is incorrect. Basicity refers to the number of ionizable \( H^+ \) ions in an acid. While \( H_2SO_4 \) can release 2 \( H^+ \) ions, it does not always do so. For example, when \( H_2SO_4 \) reacts with \( NaOH \), it can produce \( NaHSO_4 \) and water, indicating that only one \( H^+ \) ion was released in that reaction. Thus, the basicity can be 1 in certain reactions.

### Conclusion
The statement that is not applicable to \( H_2SO_4 \) is: **Acid always shows a basicity of 2.**

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