A compound used in making nylon, contains `43.8%` oxygen. There are four oxygen atoms per molecule. What is the molecular mass of compound ?

Options

A. 36
B. 116
C. 292
D. 146

Answer

To find the molecular mass of the compound used in making nylon that contains 43.8% oxygen, we can follow these steps:

### Step 1: Understand the given information
We know that the compound contains 43.8% oxygen by mass and that there are 4 oxygen atoms in each molecule of the compound.

### Step 2: Calculate the mass of oxygen in the compound
The molar mass of oxygen (O) is approximately 16 g/mol. Since there are 4 oxygen atoms in the compound, the total mass of oxygen in one molecule of the compound is:
\[ \text{Mass of oxygen} = 4 \times 16 \, \text{g/mol} = 64 \, \text{g/mol} \]

### Step 3: Set up the equation for the percentage of oxygen
The percentage of oxygen in the compound can be expressed as:
\[ \text{Percentage of oxygen} = \left( \frac{\text{Mass of oxygen}}{\text{Molecular mass of compound}} \right) \times 100 \]
Substituting the known values:
\[ 43.8 = \left( \frac{64}{M} \right) \times 100 \]
where \( M \) is the molecular mass of the compound.

### Step 4: Rearrange the equation to solve for \( M \)
Rearranging the equation gives:
\[ M = \frac{64 \times 100}{43.8} \]

### Step 5: Calculate \( M \)
Now, we can calculate \( M \):
\[ M = \frac{6400}{43.8} \approx 146.11 \, \text{g/mol} \]

### Conclusion
The molecular mass of the compound is approximately **146.11 g/mol**.

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