Predict whether each of the following compounds is soluble in water: d. Al(OH)3

Verified step by step guidance

1. Identify the compound: The compound in question is aluminum hydroxide, \( \text{Al(OH)}_3 \).
2. Recall solubility rules: Most hydroxides (OH-) are generally insoluble in water, with exceptions for alkali metals and some alkaline earth metals like Ba(OH)2.
3. Consider the cation: Aluminum (Al3+) is not an alkali metal or one of the common exceptions for hydroxide solubility.
4. Apply the solubility rule: Since Al(OH)3 does not fall under the exceptions, it is considered insoluble in water.
5. Conclude: Based on the solubility rules, \( \text{Al(OH)}_3 \) is predicted to be insoluble in water.

Key Concepts

Solubility Rules

Solubility rules are guidelines that help predict whether a compound will dissolve in water. Generally, compounds containing alkali metals, ammonium ions, and nitrates are soluble, while many hydroxides, including Al(OH)3, are often insoluble. Understanding these rules is essential for determining the solubility of various ionic compounds.

Hydroxides and Their Solubility

Hydroxides are compounds that contain the hydroxide ion (OH-). The solubility of hydroxides varies significantly; while alkali metal hydroxides are soluble, most transition metal hydroxides, including aluminum hydroxide (Al(OH)3), are generally insoluble in water. This concept is crucial for predicting the behavior of Al(OH)3 in aqueous solutions.

Ionic Compounds in Water

Ionic compounds dissociate into their constituent ions when dissolved in water, which is a polar solvent. The extent of this dissociation depends on the solubility of the compound. For Al(OH)3, its low solubility means it does not significantly dissociate in water, leading to its classification as insoluble under standard conditions.