Final answer:
Calcium salts have lower solubility, which makes sodium salts more suitable for preparations where high solubility is necessary. Sodium salts like NaCl are highly soluble because of strong ion-water attractions, while calcium salts are less soluble due to stronger ionic attractions in the solid state.
Step-by-step explanation:
The question relates to why solutions were prepared with sodium salts rather than calcium salts. The correct answer is that calcium salts have lower solubility compared to sodium salts. Solubility is a key factor because it determines how well a salt can dissolve in a solvent like water. Sodium chloride (NaCl), also known as table salt, has a favorable solubility due to the strong attraction between its ions (Na+ and Cl-) and water molecules. This process is known as ionization, where soluble salts like NaCl dissolve because their ions more strongly attract the partial positive and negative charges of water molecules, resulting in the ions separating in solution.
In contrast, calcium salts, such as calcium chloride (CaClâ‚‚), are less soluble due to the larger electrostatic attractions between their ions in a crystal, and sometimes weaker ion-dipole attractive forces between the ions and water molecules. This makes calcium salts less desirable for preparations where a highly soluble salt is needed. Additionally, sodium salts often have a more optimal balance between formula mass and solubility, leading to saturated solutions with higher concentrations than equivalent solutions using calcium salts.