Question

An alloy of copper, silver and gold is found to have copper atom constituting the ccp lattice. If silver atoms occupy the edge centres and gold atoms are present at body centres, the alloy has a formula

• A. \( Cu_4Ag_8Au \)
• B. \( Cu_4Ag_4Au \)
• C. \( Cu_4AgAu \)
• D. \( Cu_4Ag_2Au_2 \)

Hint:

The formula for an alloy can be derived from the stoichiometry based on the positions of the atoms in the unit cell and the coordination number.

Answer 1

The Correct Option is A

In a ccp lattice, the number of atoms in each unit cell is determined by the number of atoms at edge and body centres. The copper, silver, and gold atoms fit into this arrangement in the ratio \( Cu_4Ag_8Au \).