Question

1 SEP Use Graphs Look at the data in Figure 1. Fresh water has a salinity close to 0%. What is the surface tension for fresh water?

2 SEP Use Graphs Look at the data in Figure 1. Sea water has an average salinity of 3.5%. What is the surface tension for water with 3.5% salinity?

3 SEP Analyze Data Look at the data in Figure 1. Describe the relationship between the salinity of water and its surface tension.

Answer 1

I don’t have Figure 1 here — could you upload it or type the plotted values so I can read the exact numbers?

If you want an immediate, typical answer (for ~20 °C) to compare with your graph:
- Fresh water (salinity ≈ 0%): surface tension ≈ 72.8 mN/m (0.0728 N/m or 72.8 dyn/cm).
- Seawater (salinity ≈ 3.5%): surface tension ≈ 73.3–73.8 mN/m (≈0.0733–0.0738 N/m).

Relationship summary: surface tension increases slightly as salinity increases; the change over the 0–3.5% salinity range is small (on the order of ~0.5–1.0 mN/m) and is approximately linear for modest salinities.

If you upload Figure 1 or give the plotted values, I’ll read the exact surface-tension values and describe the relationship based on that specific data.