What mass of H2SO4 must be employed in the reaction `BaCl_(2)+H_(2)SO_(4)rarr BaSO_(4)+2HCl` if `2 2.08gBaCl_(2)` is used up and `2.33gBaSO4 , 0.73gHCl` are formed.

Options

A. 0.98 g
B. 1.23 g
C. 0.72 g
D. 0.49g

Answer

To find the mass of H₂SO₄ required in the reaction \( \text{BaCl}_2 + \text{H}_2\text{SO}_4 \rightarrow \text{BaSO}_4 + 2\text{HCl} \), we will follow these steps:

### Step 1: Calculate the moles of BaSO₄ produced
We know the mass of BaSO₄ produced is 2.33 g. To find the number of moles, we use the formula:

\[ \text{Moles} = \frac{\text{Mass}}{\text{Molar Mass}} \]

First, we need to calculate the molar mass of BaSO₄:
- Atomic mass of Ba = 137 g/mol
- Atomic mass of S = 32 g/mol
- Atomic mass of O = 16 g/mol (and there are 4 O atoms)

\[ \text{Molar Mass of BaSO}_4 = 137 + 32 + (4 \times 16) = 137 + 32 + 64 = 233 \text{ g/mol} \]

Now, we can calculate the moles of BaSO₄:

\[ \text{Moles of BaSO}_4 = \frac{2.33 \text{ g}}{233 \text{ g/mol}} = 0.01 \text{ moles} \]

### Step 2: Determine the moles of H₂SO₄ required
From the balanced chemical equation, we see that 1 mole of BaSO₄ is produced for every 1 mole of H₂SO₄ used. Therefore, the moles of H₂SO₄ required will also be 0.01 moles.

### Step 3: Calculate the mass of H₂SO₄ needed
Now, we need to find the mass of H₂SO₄ corresponding to 0.01 moles. First, we calculate the molar mass of H₂SO₄:
- Atomic mass of H = 1 g/mol (and there are 2 H atoms)
- Atomic mass of S = 32 g/mol
- Atomic mass of O = 16 g/mol (and there are 4 O atoms)

\[ \text{Molar Mass of H}_2\text{SO}_4 = (2 \times 1) + 32 + (4 \times 16) = 2 + 32 + 64 = 98 \text{ g/mol} \]

Now we can calculate the mass of H₂SO₄ required:

\[ \text{Mass of H}_2\text{SO}_4 = \text{Moles} \times \text{Molar Mass} = 0.01 \text{ moles} \times 98 \text{ g/mol} = 0.98 \text{ g} \]

### Final Answer
The mass of H₂SO₄ that must be employed in the reaction is **0.98 g**.

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