Provided that the solubility measurement in this question is understood to be in 100.0 g of water, the answer is NaCl.
Scroll through the pages below to find answers to some of the most frequently asked questions about solubility curves.
The solubility of a substance is the amount of that substance that will dissolve in a given amount of solvent. Solubility is a quantitative term. Solubilities vary enormously.
The terms soluble and insoluble are relative. A substance is said to be soluble if more than 0.1 g of that substance dissolves in 100 mL solvent. If less than 0.1 g dissolves in 100 mL solvent, the substance is said to be insoluble or, more exactly, sparingly soluble.
The terms miscible and immiscible may be encountered when considering the solubility of one liquid in another. Miscible means soluble without limits; for example, alcohol is miscible with water. Immiscible and insoluble mean the same; oil is immiscible with water, as in oil and vinegar salad dressing.
To learn more, refer to www.chem.wisc.edu - Solubility.
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