Question

BCC crystal structure is exhibited by

• A. Chromium
• B. Copper
• C. Magnesium
• D. Titanium

Hint:

It's helpful to memorize the crystal structures of common metals. A simple grouping:

• BCC: Fe(\(\alpha\)), Cr, W, Mo, V

• FCC: Al, Cu, Ni, Ag, Au, Pb

• HCP: Mg, Zn, Ti(\(\alpha\)), Co(\(\alpha\)), Cd

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Crystal structure refers to the ordered arrangement of atoms, ions, or molecules in a crystalline material. Different metals crystallize into different structures. The most common metallic crystal structures are Body-Centered Cubic (BCC), Face-Centered Cubic (FCC), and Hexagonal Close-Packed (HCP). The question asks to identify which of the given metals has a BCC structure.

Step 2: Detailed Explanation:
Let's examine the common crystal structures of the metals listed in the options at room temperature:

• Chromium (Cr): Chromium is a classic example of a metal that has a Body-Centered Cubic (BCC) crystal structure.

• Copper (Cu): Copper has a Face-Centered Cubic (FCC) crystal structure. It is known for its high ductility, which is a characteristic of FCC metals.

• Magnesium (Mg): Magnesium has a Hexagonal Close-Packed (HCP) crystal structure.

• Titanium (Ti): At room temperature, Titanium has an HCP structure (called \(\alpha\)-Ti). It undergoes an allotropic transformation to a BCC structure (called \(\beta\)-Ti) at high temperatures (above 882°C).
Based on this analysis, Chromium is the metal among the options that exhibits a BCC crystal structure under standard conditions.

Step 3: Final Answer:
Among the given options, Chromium (Cr) is the metal that exhibits a Body-Centered Cubic (BCC) crystal structure at room temperature.