Question

the arrangement of water molecules around an ion is called a hydration sphere (also sphere of hydration). this process takes place when a substance dissolves in water - its ions become surrounded by water molecules. which of the particles below would water form a hydration sphere around? note that ions are particles with a full + or - charge. na* and cl - are both ions. having a charge like this attracts water molecules, which are polar (i.e., they have regions of partial positive and negative charge). when water is attracted to an ion, it surrounds it, dissolving it in a sphere of hydration. this applies to most ions.

Explanation:

Step1: Analyze the nature of each particle

• \(Li^{+}\) is an ion. According to the text, ions (with full + or - charge) attract polar water molecules. So water will form a hydration sphere around \(Li^{+}\).
• \(Fe\) is a neutral atom. Neutral atoms do not have a full + or - charge to strongly attract polar water molecules in the way ions do. So water will not form a hydration sphere around \(Fe\).
• \(Cl^{-}\) is an ion. Ions (with full + or - charge) attract polar water molecules. So water will form a hydration sphere around \(Cl^{-}\).
• \(Mg^{2 +}\) is an ion. Ions (with full + or - charge) attract polar water molecules. So water will form a hydration sphere around \(Mg^{2+}\).
• \(Ni\) is a neutral atom. Neutral atoms do not have a full + or - charge to strongly attract polar water molecules in the way ions do. So water will not form a hydration sphere around \(Ni\).

Answer:

\(Li^{+}\), \(Cl^{-}\), \(Mg^{2+}\)