Metallic Bonding in Alloys

Steps:

• Define alloy as a mixture of metals or metal with non-metal, sharing metallic properties.
• Examine option A: Alloys involve many metals, not just copper.
• Examine option B: High carbon steel is hard due to carbon content, opposite of soft.
• Examine option C: Matches metallic bonding model with positive ions in electron sea.
• Examine option D: Alloys like brass lack fixed ratios, unlike compounds.

Why C is correct:

• Alloys exhibit metallic bonding, where attraction between positive metal ions and delocalized 'sea of electrons' explains conductivity and malleability (delocalized electron model).

Why the others are wrong:

• A: Alloys form from various metals, e.g., steel (iron-carbon) or bronze (copper-tin).
• B: High carbon steel is brittle and hard, not soft and shapeable like low carbon.
• D: Brass (copper-zinc) is a variable mixture without a chemical formula like ionic compounds.

Final answer: C