00:03
Here we are investigating a face -centered cubic, where the face -centered cubic unit cell has four entire atoms within it.
00:10
So firstly, what we can do is determine the weight of a gold unit cell.
00:15
So we have four atoms of gold, a u, not a -g, divided by the unit cell, multiplied by one mole of gold, divided by avogadro's number of gold atoms, multiplied by the mass, 196 .97 grams divided by one mole a u.
00:43
This leaves us with 1 .31 times 10 to the minus 21 grams of gold per unit cell.
00:58
And so then we can solve for volume using the equation that is density is equal to mass over volume, where the volume is equal to the mass over the density.
01:14
But we should get is 6 .79 times 10 to the minus 23 centimeters cubed for our volume.
01:24
And so next what we can do is determine a side length where the side length is cubed...