Consider the compound Al(OH)_3. What type of solid does it form?

• A. Covalent (network) solid
• B. Molecular solid
• C. Hydrated (amorphous) solid
• D. Ionic solid

Answer: (C)

Verified step by step guidance

1. Identify the nature of the compound Al(OH)\_3 by examining its constituent elements: aluminum (Al) is a metal and hydroxide (OH) is a polyatomic ion.
2. Recognize that Al(OH)\_3 consists of aluminum cations (Al^{3+}) and hydroxide anions (OH^{-}), which typically form ionic bonds due to the metal-nonmetal interaction.
3. Understand that ionic solids are composed of ions held together by strong electrostatic forces in a lattice structure, which is common for metal hydroxides like Al(OH)\_3.
4. Consider the physical form of Al(OH)\_3, which is often found as a hydrated or amorphous solid rather than a well-defined crystalline ionic lattice, due to water molecules incorporated in its structure or lack of long-range order.
5. Conclude that Al(OH)\_3 does not form a covalent network solid or a molecular solid, but rather forms a hydrated (amorphous) solid with ionic character.