In sulphur estimation, 0.471 g of an organic compound gave 1.4439 g of barium sulphate. The percentage of sulphur in the compound is ________(Nearest integer)(Given : Atomic mass Ba : 137 u, S : 32 u, O : 16 u)

Answer

To find the percentage of sulfur in the organic compound, we will follow these steps:

### Step 1: Calculate the moles of barium sulfate (BaSO₄)
The molar mass of barium sulfate (BaSO₄) can be calculated using the atomic masses:
- Atomic mass of Ba = 137 u
- Atomic mass of S = 32 u
- Atomic mass of O = 16 u (there are 4 oxygen atoms in BaSO₄)

Molar mass of BaSO₄ = 137 + 32 + (4 × 16)
= 137 + 32 + 64
= 233 g/mol

Now, we can calculate the moles of BaSO₄ produced from the given mass:
\[ \text{Moles of BaSO₄} = \frac{\text{mass of BaSO₄}}{\text{molar mass of BaSO₄}} = \frac{1.4439 \, \text{g}}{233 \, \text{g/mol}} \approx 0.00619 \, \text{mol} \]

### Step 2: Calculate the moles of sulfur (S)
From the formula of barium sulfate (BaSO₄), we see that 1 mole of BaSO₄ contains 1 mole of sulfur (S). Therefore, the moles of sulfur in the sample is equal to the moles of BaSO₄:
\[ \text{Moles of S} = 0.00619 \, \text{mol} \]

### Step 3: Calculate the mass of sulfur
Now, we can calculate the mass of sulfur using its molar mass:
\[ \text{Mass of S} = \text{moles of S} \times \text{molar mass of S} = 0.00619 \, \text{mol} \times 32 \, \text{g/mol} \approx 0.197 \, \text{g} \]

### Step 4: Calculate the percentage of sulfur in the organic compound
The percentage of sulfur in the organic compound can be calculated using the formula:
\[ \text{Percentage of S} = \left( \frac{\text{mass of S}}{\text{mass of organic compound}} \right) \times 100 \]
Substituting the values:
\[ \text{Percentage of S} = \left( \frac{0.197 \, \text{g}}{0.471 \, \text{g}} \right) \times 100 \approx 41.8\% \]

Rounding to the nearest integer, the percentage of sulfur in the compound is **42%**.