how can you determine the diameter of an atom. I looked it up and it said the average diameter is 10^-8 but how did they get that number?
2007-06-04 14:07:31 · 3 answers · asked by Lynn M 1 in Science & Mathematics ➔ Chemistry
Iron is near the middle of the periodic table. Let's use it for an example.
The density of iron is 7.86 grams per cubic centimeter. A mole (a standard chemical measure) of any element weighs its gram-molecular weight (in this case 55.845 grams) and consists of 6.02E23 atoms. (The E23 notation means "shift the decimal point 23 places to the right).
At 7.86 grams per CC, it takes 7.105 CCs to make a mole. Divide by 6.02E23 and you find that the volume of an iron atom is 1.18E-23 centimeter.
The relationship between radius and volume of a sphere is 4/3 PI R**3 (the notation **3 means "to the third power"). Applied to the above number, we find that the radius of an iron atom is 1.412E-8 centimeters. We need to double that to get the radius, and it's 2.8E-8 centimeters. or in meters, 2.8E-10 meters.
2007-06-04 14:50:27 · answer #1 · answered by Anonymous · 0⤊ 0⤋
look up the atomic radius on the table of the elements and multiply by 2
2007-06-04 14:12:01 · answer #2 · answered by Sam 2 · 0⤊ 0⤋
Hi. Start here http://www.phys.unsw.edu.au/einsteinlight/jw/module6_Planck.htm
2007-06-04 14:11:55 · answer #3 · answered by Cirric 7 · 0⤊ 0⤋