In the estimation of sulphur by carius methode 0.480g of organic compound give `0.699`g of Barium sulphate. The percentage of
sulphur in the compound is (Atomic masses , Ba=137, S=32, O=16)

Options

A. `15%`
B. `35%`
C. `20%`
D. `30%`

Answer

To find the percentage of sulfur in the organic compound using the Carius method, we can follow these steps:

### Step 1: Identify the given data
- Mass of the organic compound = 0.480 g
- Mass of barium sulfate (BaSO4) formed = 0.699 g
- Atomic masses: Ba = 137 g/mol, S = 32 g/mol, O = 16 g/mol

### Step 2: Calculate the molar mass of barium sulfate (BaSO4)
The molar mass of BaSO4 can be calculated as follows:
\[ \text{Molar mass of BaSO4} = \text{Mass of Ba} + \text{Mass of S} + 4 \times \text{Mass of O} \]
\[ = 137 + 32 + 4 \times 16 = 137 + 32 + 64 = 233 \text{ g/mol} \]

### Step 3: Determine the mass of sulfur in the barium sulfate
From the stoichiometry of the reaction, we know that 233 g of BaSO4 contains 32 g of sulfur. We can set up a proportion to find the mass of sulfur in 0.699 g of BaSO4:
\[ \text{Mass of S in BaSO4} = \left(\frac{32 \text{ g S}}{233 \text{ g BaSO4}}\right) \times 0.699 \text{ g BaSO4} \]
\[ = \frac{32 \times 0.699}{233} \approx 0.096 \text{ g S} \]

### Step 4: Calculate the percentage of sulfur in the organic compound
Now we can calculate the percentage of sulfur in the organic compound using the formula:
\[ \text{Percentage of S} = \left(\frac{\text{Mass of S}}{\text{Mass of organic compound}}\right) \times 100 \]
\[ = \left(\frac{0.096 \text{ g}}{0.480 \text{ g}}\right) \times 100 \approx 20\% \]

### Final Answer
The percentage of sulfur in the organic compound is approximately **20%**.

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