Crystal Lattice Structures: Density Calculation 2

The video tutorial explains how to calculate the radius of an element given its unit cell length in a face-centered cubic lattice. It covers the concepts of unit cell length, volume, and density, and demonstrates the calculation using a specific formula. The tutorial emphasizes the importance of using the correct denominator expression and provides a step-by-step guide to finding the radius, ensuring the result is reasonable.

What is the unit cell length of the element mentioned in the problem?

• 7.21 angstroms

• 6.21 angstroms

• 5.21 angstroms

• 4.21 angstroms

In a face-centered cubic lattice, what is the relationship between the unit cell length and the radius?

• A naught = 2√2r

• A naught = 4r

• A naught = 3r

• A naught = 2r

What is the formula used to calculate the radius of the element from the unit cell length?

• r = A naught / 2

• r = A naught / 3

• r = A naught / 2^(3/2)

• r = A naught / 2√2

What is the approximate radius of the element calculated in the video?

• 2.84 angstroms

• 3.84 angstroms

• 1.84 angstroms

• 4.84 angstroms

Why is it important to check the reasonableness of the calculated radius?

• To confirm the type of lattice

• To check the accuracy of the density formula

• To verify the unit cell length

• To ensure it is not too small or too large compared to typical atomic radii