0.2595 g of organic compound when treated by carius method gave 0.35 g of `BaSO_(4)`. Calculate the percentage of sulphur in the compound.

Explanation

To calculate the percentage of sulfur in the organic compound, we can follow these steps:

### Step 1: Determine the molar mass of barium sulfate (BaSO₄)
- The molar mass of BaSO₄ can be calculated as follows:
- Molar mass of Ba = 137 g/mol
- Molar mass of S = 32 g/mol
- Molar mass of O = 16 g/mol (and there are 4 oxygen atoms)

Therefore, the molar mass of BaSO₄ = 137 + 32 + (4 × 16) = 137 + 32 + 64 = 233 g/mol.

### Step 2: Calculate the moles of barium sulfate produced
- We know that 0.35 g of BaSO₄ was produced. To find the number of moles of BaSO₄, we use the formula:

\[ \text{Moles of BaSO₄} = \frac{\text{mass of BaSO₄}}{\text{molar mass of BaSO₄}} = \frac{0.35 \, \text{g}}{233 \, \text{g/mol}} \approx 0.0015 \, \text{mol} \]

### Step 3: Determine the moles of sulfur in the organic compound
- Each mole of BaSO₄ contains one mole of sulfur (S). Therefore, the moles of sulfur in the organic compound is also 0.0015 mol.

### Step 4: Calculate the mass of sulfur in the organic compound
- The mass of sulfur can be calculated using its molar mass:

\[ \text{Mass of S} = \text{moles of S} \times \text{molar mass of S} = 0.0015 \, \text{mol} \times 32 \, \text{g/mol} = 0.048 \, \text{g} \]

### Step 5: Calculate the percentage of sulfur in the organic compound
- Finally, we can calculate the percentage of sulfur in the organic compound using the formula:

\[ \text{Percentage of S} = \left( \frac{\text{mass of S}}{\text{mass of organic compound}} \right) \times 100 = \left( \frac{0.048 \, \text{g}}{0.2595 \, \text{g}} \right) \times 100 \approx 18.52\% \]

### Final Answer
The percentage of sulfur in the organic compound is approximately **18.52%**.

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