Certainly! Let's analyze and solve the problem step by step.
1. Identify the given quantities:
- Mass of the seawater sample: [tex]\(520 \text{ grams}\)[/tex]
- Moles of NaCl in the sample: [tex]\(0.317 \text{ moles}\)[/tex]
- Molar mass of NaCl: [tex]\(58.44 \text{ g/mol}\)[/tex]
2. Calculate the mass of NaCl in the sample:
We can determine the mass of NaCl by using the relationship:
[tex]\[
\text{Mass of NaCl} = \text{Moles of NaCl} \times \text{Molar mass of NaCl}
\][/tex]
Substituting the values:
[tex]\[
\text{Mass of NaCl} = 0.317 \text{ moles} \times 58.44 \text{ g/mol} = 18.52548 \text{ grams}
\][/tex]
3. Calculate the percentage composition of NaCl in the seawater:
The percent composition can be calculated with the formula:
[tex]\[
\text{Percent composition of NaCl} = \left( \frac{\text{Mass of NaCl}}{\text{Total mass of the sample}} \right) \times 100
\][/tex]
Substituting the values:
[tex]\[
\text{Percent composition of NaCl} = \left( \frac{18.52548 \text{ grams}}{520 \text{ grams}} \right) \times 100 \approx 3.56\%
\][/tex]
After following these steps, we find that the percentage composition of NaCl in the seawater is approximately [tex]\(3.6\%\)[/tex]. Thus, the correct answer is:
C. [tex]\(3.6\%\)[/tex]