Number of results: 74
I have a problem set due tomorrow, and two problems in it were not covered in class. The first is this: Molybdenum has an atomic radius of 0.145 nm. The volume of its cubic unit cell is 0.0375 nm^3. What is the geometry of the molybdenum unit cell? I have no idea where to even...
Thursday, December 7, 2006 at 6:04pm by chris
I get 33.333% The each unit of energy has 3 possible landing. So the total possibilities are 3*3*3 = 27. There are 3 ways in which B has one unit and is the first unit. (BAA, BAC, BCC). So, there must also be 3 ways where B gets the second unit and 3 ways where B gets the ...
Monday, October 22, 2007 at 10:58pm by economyst
I think the answers probably are that the edge lengths are the same; i.e., a = b = c and all the angles are the same. The angles are 90 degrees in all cases. The way I read the question, however, it seems to ask what is true for ALL three of the cubic lattices. And the answer ...
Tuesday, February 12, 2008 at 2:34am by DrBob222
Body centered cubic lattices (bcc) and simple cubic lattices are not close packed; therfore, the spheres touch on the sides and top and bottom but one layer doesn't fit into the holes of another layer as the close packed layers do. So AAAA would be the way to describe the ...
Tuesday, February 12, 2008 at 2:08am by DrBob222
Find the unit cell (simple, bcc, fcc), type of holes where the smaller ions are found (tetrahedral, octrahedral, cubic), and number of cations and anions per unit cell for the following compounds: CdSe CsI Li2O KBr NaCl ZnS(I)
Tuesday, February 12, 2008 at 10:35pm by jina
There are two Li atoms per unit cell for a bcc structure. mass = 2*massofmole Li/6.022 x 10^23 = mass of unit cell. You know the volume. density = mass/volume.
Saturday, February 21, 2009 at 6:03pm by DrBob222
The element lithium has bcc packing with a body-centered cubic unit cell. The volume of the unit cell is 4.32 x 10-26 L. Calculate the density (g/cm3) of the element.
Saturday, February 21, 2009 at 6:03pm by tweety
The element K has bcc packing with a body-centered cubic unit cell. The density of K is 0.862 g/mL. Calculate the volume (L) of the unit cell of K.
Saturday, February 21, 2009 at 6:05pm by tweety
The element Rb has bcc packing with a body-centered cubic unit cell. The density of Rb is 1.532 g/cm3 and the cell volume is 1.852 x 10-22 mL. Calculate the value of Avogadro's number to three significant figures based on these data.
Saturday, February 21, 2009 at 6:05pm by tweety
yo what were your type of holes for this problem?? the type of packing for bcc is A-B-A
Monday, February 18, 2008 at 9:02pm by poopoopoo
BCC crystal structure, atomic radius of .1363, and an atomic weight of 95.94g/mol. How would you compute the theoretical density?
Tuesday, September 15, 2009 at 1:16pm by Z32
My best guess is that this is 136.3 pm which converts to 136.3 x 10^-9 m or 1.363 x 10^-8 cm. Then d (the diagonal in the bcc) is 4r = 4 x 1.353 x 10^-8 = 4.452 x 10^-8 cm and d^2 = 3a^2. Solve for a and I get 3.148 x 10^-8 cm and volume is a^3 = ?? mass of unit cell is 2 ...
Tuesday, September 15, 2009 at 1:16pm by DrBob222
bcc means 2 atoms per unit cell. mass of unit cell is 2*55.847/6.022 x 10^23 = ?? g/unit cell. mass = volume x density or volume = mass/density = ??g/7.86 g/cc = xx cc a (the edge length) = volume1/3 for a bcc crystal, radius = (a/4)*31/2. Check my thinking. I obtained 2.87 x ...
Saturday, November 14, 2009 at 11:50am by DrBob222
what is the number of each atom in the unit cell of a BCC cystalline structure unit cell. I know its 2 atoms=8/8 +1 Calculate what % of each atom is contained within the unit cell? How do I do this
Wednesday, January 13, 2010 at 10:46pm by Anonymous
This is math?? Yes, there are two atoms/unit cell in a bcc. I don't know how much information you have but the general idea is to calculate the volume of the unit cell (vol = mass/density), then calculate the volume of the two atoms [(4/3)*pi*r^3 for each of the two atoms]. ...
Wednesday, January 13, 2010 at 10:46pm by DrBob222
Is the calculation of percentage of each atom within a Body centered cubic cell AKA volume of the BCC cell same as the atomic packing factor for the BCC unit cell. The BCC % is 68%. the atomic packing factor is just 0.68. Am I completely wrong? And also how do i calculate the ...
Wednesday, January 13, 2010 at 11:58pm by Anonymous
No. The bcc is 68% and the factor is, of course, 0.68. Fe is a bcc, also, and if you know r, then 4r = a(3)2 and you can calculate a. Here is a site that gives a,b,c and much more information about iron. a, b, and c are about 286 something pm. The volume would, of course, be ...
Wednesday, January 13, 2010 at 11:58pm by DrBob222
An element has bcc packing with a body-centered cubic unit cell. Its density is 19300 kg/m3 and the unit cell volume is 3.17 x 10-26 L. Calculate the molar mass (g/mol) of the element to three significant figures. The element rubidium has bcc packing with a body-centered cubic...
Monday, February 8, 2010 at 9:47pm by Dan
Remember these. A bcc unit cell has 2 atoms/unit cell. A fcc unit cell has 4 atoms/unit cell. A simple cubic unit cell has 1 atom/unit cell.
Monday, February 8, 2010 at 9:47pm by DrBob222
how do i calculate the volume of a unit cell and volume of atoms within a unit cell for FCC and BCC
Thursday, February 11, 2010 at 1:37am by blasting