Solubility curves can be used for comparing the solubility of different substances at a given temperature .

Answer

**Step-by-Step Solution:**

1. **Understanding Solubility Curves:**
- A solubility curve is a graphical representation that shows how the solubility of a substance changes with temperature. It typically plots temperature on the x-axis and solubility (usually in grams of solute per 100 grams of solvent) on the y-axis.

2. **Purpose of Solubility Curves:**
- The primary purpose of solubility curves is to compare the solubility of different substances at a specific temperature. By looking at the curve, one can easily determine how much of each substance can dissolve in a given amount of solvent at that temperature.

3. **Comparing Solubility:**
- To compare the solubility of different substances using their solubility curves, you would look at the points on the graph where each substance's curve intersects with a horizontal line drawn at the temperature of interest. The height of each curve at that temperature indicates the solubility of each substance.

4. **Analyzing Data:**
- If you have multiple substances plotted on the same graph, you can directly compare their solubility. For example, if substance A's curve is higher than substance B's curve at a specific temperature, it means that substance A is more soluble than substance B at that temperature.

5. **Conclusion:**
- In summary, solubility curves are valuable tools for comparing the solubility of various substances at a specific temperature, providing a clear visual representation of how different factors affect solubility.

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