Calculate the percentage of N in urea. (Molar mass of urea `= 60" g mol"^(-1)` )

Answer

To calculate the percentage of nitrogen (N) in urea, we can follow these steps:

### Step 1: Identify the chemical formula of urea
Urea has the chemical formula \( \text{NH}_2\text{CO}\text{NH}_2 \). This indicates that there are two nitrogen atoms in each molecule of urea.

### Step 2: Determine the molar mass of nitrogen
The molar mass of nitrogen (N) is approximately \( 14 \, \text{g/mol} \).

### Step 3: Calculate the total mass of nitrogen in urea
Since there are two nitrogen atoms in urea, the total mass of nitrogen in one mole of urea can be calculated as follows:
\[ \text{Total mass of N} = 2 \times \text{molar mass of N} = 2 \times 14 \, \text{g} = 28 \, \text{g} \]

### Step 4: Find the molar mass of urea
The molar mass of urea is given as \( 60 \, \text{g/mol} \).

### Step 5: Calculate the percentage of nitrogen in urea
The percentage of nitrogen in urea can be calculated using the formula:
\[ \text{Percentage of N} = \left( \frac{\text{Mass of N}}{\text{Molar mass of urea}} \right) \times 100 \]
Substituting the values:
\[ \text{Percentage of N} = \left( \frac{28 \, \text{g}}{60 \, \text{g}} \right) \times 100 \]

### Step 6: Perform the calculation
\[ \text{Percentage of N} = \left( \frac{28}{60} \right) \times 100 = 46.67\% \]

### Final Answer
The percentage of nitrogen in urea is approximately \( 46.67\% \).

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