Copper crystallizes in an FCC lattice with a unit cell edge length of . What is the approximate atom — Solid State Chemistry Question

💡 Solution & Explanation

For FCC, atoms touch along the face diagonal, so $4r=\sqrt{2}a$. Thus $r=\frac{a}{2\sqrt{2}}=\frac{361}{2\times1.414}\text{ pm}\approx128\text{ pm}$.