The formula weight of `H_(2)SO_(4)` is 98. The weight of the acid in 400 mL 0.1 M solution is

Options

A. 2.45 g
B. 3.92 g
C. 4.90 g
D. 9.8 g

Explanation

To find the weight of sulfuric acid (H₂SO₄) in a 400 mL solution with a molarity of 0.1 M, we can follow these steps:

### Step 1: Understand the formula for molarity
Molarity (M) is defined as the number of moles of solute per liter of solution. The formula is:
\[ \text{Molarity} = \frac{\text{Number of moles}}{\text{Volume in liters}} \]

### Step 2: Convert volume from mL to L
We have 400 mL of solution. To convert this to liters:
\[ 400 \, \text{mL} = \frac{400}{1000} \, \text{L} = 0.4 \, \text{L} \]

### Step 3: Calculate the number of moles of H₂SO₄
Using the molarity formula, we can rearrange it to find the number of moles:
\[ \text{Number of moles} = \text{Molarity} \times \text{Volume in liters} \]
Substituting the values:
\[ \text{Number of moles} = 0.1 \, \text{M} \times 0.4 \, \text{L} = 0.04 \, \text{moles} \]

### Step 4: Calculate the weight of H₂SO₄
To find the weight of the acid, we use the formula:
\[ \text{Weight} = \text{Number of moles} \times \text{Molar mass} \]
The molar mass of H₂SO₄ is given as 98 g/mol. Substituting the values:
\[ \text{Weight} = 0.04 \, \text{moles} \times 98 \, \text{g/mol} = 3.92 \, \text{grams} \]

### Final Answer
The weight of sulfuric acid in the 400 mL 0.1 M solution is **3.92 grams**.

---