For preparing 0.1 M solution of `H_(2)SO_(4)` in one litre, we need
`H_(2)SO_(4)`

Options

A. `0.98g`
B. `4.9g`
C. `49.0g`
D. `9.8g`

Answer

To prepare a 0.1 M solution of H₂SO₄ in one litre, we need to calculate the mass of H₂SO₄ required. Here’s the step-by-step solution:

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

### Step 2: Rearrange the formula to find moles
To find the number of moles of solute, we can rearrange the formula:
\[ \text{Number of moles} = \text{Molarity} \times \text{Volume} \]

### Step 3: Substitute the given values
We know the molarity is 0.1 M and the volume is 1 litre. Therefore:
\[ \text{Number of moles of H₂SO₄} = 0.1 \, \text{M} \times 1 \, \text{L} = 0.1 \, \text{moles} \]

### Step 4: Calculate the molar mass of H₂SO₄
The molar mass of H₂SO₄ can be calculated as follows:
- Hydrogen (H): 1 g/mol × 2 = 2 g/mol
- Sulfur (S): 32 g/mol × 1 = 32 g/mol
- Oxygen (O): 16 g/mol × 4 = 64 g/mol

Adding these together:
\[ \text{Molar mass of H₂SO₄} = 2 + 32 + 64 = 98 \, \text{g/mol} \]

### Step 5: Use the number of moles to find the mass
Now, we can use the number of moles to find the mass of H₂SO₄ required:
\[ \text{Mass} = \text{Number of moles} \times \text{Molar mass} \]
\[ \text{Mass} = 0.1 \, \text{moles} \times 98 \, \text{g/mol} = 9.8 \, \text{grams} \]

### Conclusion
To prepare a 0.1 M solution of H₂SO₄ in one litre, we need **9.8 grams** of H₂SO₄.

---