If the molecular weight of `H_(2)SO_(4)` is 98. The amount of acid present in 400 ml of 0.1 molar solution of acid will be

Options

A. 2.45 g
B. 3.92 g
C. 4.90 g
D. 9.80 g

Explanation

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

### Step 1: Convert the volume from mL to L
The volume of the solution is given as 400 mL. To convert this to liters, we use the conversion factor that 1 L = 1000 mL.

\[ \text{Volume in L} = \frac{400 \text{ mL}}{1000} = 0.4 \text{ L} \]

### Step 2: Use the molarity formula to find the number of moles
Molarity (M) is defined as the number of moles of solute divided by the volume of solution in liters. Rearranging the formula gives us:

\[ \text{Number of moles} = \text{Molarity} \times \text{Volume in L} \]

Substituting the values:

\[ \text{Number of moles} = 0.1 \text{ mol/L} \times 0.4 \text{ L} = 0.04 \text{ moles} \]

### Step 3: Calculate the weight of H₂SO₄ using its molecular weight
We know that the molecular weight of H₂SO₄ is 98 g/mol. We can find the weight of H₂SO₄ using the formula:

\[ \text{Weight} = \text{Number of moles} \times \text{Molecular weight} \]

Substituting the values:

\[ \text{Weight} = 0.04 \text{ moles} \times 98 \text{ g/mol} = 3.92 \text{ grams} \]

### Final Answer
The amount of H₂SO₄ present in 400 mL of a 0.1 molar solution is **3.92 grams**.

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