Determining the density of Silicon

Thread starter weston_sagle
Start date Oct 13, 2009
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Density Silicon

AI Thread Summary

The density of silicon can be calculated using its unit cell structure, which contains 8 atoms. Given the atomic weight of silicon is 28.09 and the lattice constant is 5.43 angstroms, the conversion of the lattice constant to centimeters is essential. The density formula results in 8 atoms per cubic centimeter, calculated as 8 divided by the volume of the unit cell in cubic centimeters. This yields a density of approximately 4.99 x 10^22 atoms/cm^3. The calculation demonstrates the straightforward relationship between atomic structure and density in silicon.

Oct 13, 2009

weston_sagle

Homework Statement

There are 8 atoms in a unit cell of Si. Silicon has an atomic weight of 28.09 and a lattice constant equal to 5.43 A. Determine the density of silicon/

Homework Equations

The Attempt at a Solution

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Oct 13, 2009

weston_sagle

Figured it out.
5.43 is in angstroms, which is 10^-8 cm.
So density is atoms for cm^3

so 8/(5.43x10^-8)^3 = 4.99x10^22/cm^3

Simple as that.

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