Final answer:
A precipitate may form in a TPN if calcium gluconate and potassium phosphate are added improperly, due to precipitation reactions between ions that create insoluble compounds.
Step-by-step explanation:
If calcium gluconate and potassium phosphate are added in the wrong order or too high of a volume in a TPN, a precipitate may form from non-soluble particles. This occurs because ions in solution can react to form new substances that are insoluble, leading to a precipitation reaction. For example, a precipitate forms in a double-replacement reaction when the cations from one reactant combine with the anions from the other reactant to form an insoluble ionic compound, such as when potassium iodide and lead (II) nitrate are mixed.
The subject here is related to the Solubility Product, which describes the dynamic equilibrium that is established when a slightly soluble ionic compound dissolves in water, forming a solution of its ions. This product, commonly denoted as Ksp, indicates the concentration of ions at which a substance will precipitate from the solution.
Regarding a specific example, the precipitation of calcium oxalate is a similar scenario where calcium ions react with oxalate ions to form an insoluble compound, which in the case of blood serum would prevent clotting. The specific concentrations of ionic species in solution will determine whether a precipitate forms based on the solubility product (Ksp) of the precipitating compound.