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rocketnuts
Feb 4, 2007, 10:12 AM
the density of solid NaCl is 2.165g/cm^3 and the distance between centers of adjacent Na+ and Cl- is 0.2819 nm.
a. Calculate the edge lenth of a cube containign one mole of NaCl.
b. Calculate the number of Na+ plus Cl- ions along one edge of the cube.
c. Calculate the Avogadro Number

Please show work if possible.

Nosnosna
Feb 4, 2007, 10:42 AM
a) You know that the weight in grams of one mole of a substance is equal to its atomic weight. Find out the number of cubic centimeters that is, and then measure the edge.
b) You're given the distance between adjacent nuclei, and you now know the length of the edge. How many times does the distance between nuclei go into that edge length?
c) Avogadro's Number is the number of molecules in a mole. Since you have the number of molecules along the edge of the cube, you can use that to calculate the total number of molecules.