Quiz 2 potential problems ChE 350 sp09

Quiz 2 potential problems ChE 350 sp09 - 3 FCC crystal...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Sample question for ChE 350 Fall 2009 Quiz 2 Name:________________________ 1 1. Determine the packing fraction of atoms in a simple cubic lattice. (or bcc, fcc or diamond cubic). 2. On the unit cell drawn below, sketch the diamond cubic unit cell; label the atoms corresponding to the fcc sublattice; with sticks corresponding to bonds, indicate one carbon tetrahedron within the diamond lattice. . 3.. Sketch the unit cell of silicon. How many atoms are included in the unit cell? List the atomic positions of the atoms. 4. Calculate the atomic radius of a gold atom, considering that it has a density of 19.30 g/cm
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 3 , FCC crystal structure, and a molecular weight of 196.97 g/mol. 5. What is the atomic density of silicon (in units of atoms/cm 3 ), considering that it has diamond cubic crystal structure, a density of 2.33 g/cm 3 , and a molecular weight of 28.085 g/mol. [yes, for the quiz, you should memorize the packing density of a diamond cubic lattice: 0.34] If boron atoms are added to a crystal of silicon (i.e., the Si is doped with boron) at a concentration of 10-16 cm-3 , what is the atomic fraction of boron atoms per silicon atoms in the crystal?...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online