A organic compound contains 4% sulphur. Its minimum molecular weight is

Options

A. 200
B. 400
C. 800
D. 1600

Explanation

To find the minimum molecular weight of an organic compound that contains 4% sulfur, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Percentage Composition**:
The problem states that the organic compound contains 4% sulfur. This means that in 100 grams of the compound, there are 4 grams of sulfur.

2. **Determine the Mass of Sulfur**:
From the percentage, we know:
\[ \text{Mass of sulfur} = 4\% \text{ of total mass of the compound} = 4 \text{ grams} \]

3. **Use the Molar Mass of Sulfur**:
The molar mass of sulfur (S) is approximately 32 grams/mol.

4. **Calculate the Total Mass of the Compound**:
If 4 grams of sulfur corresponds to 4% of the total mass of the compound, we can set up the equation:
\[ \text{Total mass of the compound} = \frac{\text{Mass of sulfur}}{\text{Percentage of sulfur}} = \frac{4 \text{ grams}}{0.04} = 100 \text{ grams} \]

5. **Find the Minimum Molecular Weight**:
To find the minimum molecular weight of the compound, we can use the ratio of the mass of sulfur to the percentage:
\[ \text{Minimum Molecular Weight} = \frac{100 \text{ grams}}{4\%} \times \text{Molar mass of sulfur} \]
Since we have already calculated that the total mass of the compound is 100 grams, we can relate it to the mass of sulfur:
\[ \text{Minimum Molecular Weight} = \frac{100 \text{ grams}}{4 \text{ grams}} \times 32 \text{ grams/mol} = 800 \text{ grams/mol} \]

6. **Conclusion**:
Therefore, the minimum molecular weight of the organic compound is 800 grams/mol.

### Final Answer:
The minimum molecular weight of the organic compound is **800 grams/mol**.