Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−4 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in this Si crystal?

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what is value for silicon in gallium

Don't give an answer. Just explain step by step by inserting the data above into the formula. So we can understand how to answer.

This is a question from the second midterm of 3.091x by edx. Stop cheating, it's silly and pointless.

To calculate the density of free charge carriers in the silicon crystal, we need to know the atomic percent of gallium in the crystal and the density of silicon atoms.

1. Convert the atomic percent of gallium into a decimal by dividing it by 100:
Gallium atomic percent = 3.091×10−4 atomic percent
Gallium atomic percent (decimal) = 3.091×10−4 / 100

2. Determine the number of gallium atoms per unit volume in the silicon crystal by multiplying the atomic percent (decimal) by the density of silicon atoms:
Number of gallium atoms per unit volume = Gallium atomic percent (decimal) * Density of silicon atoms

3. Calculate the number density of free charge carriers using the relationship:
Density of free charge carriers = Number of gallium atoms per unit volume * Avogadro's number

Let's plug in the numbers and perform the calculations:

First, we need to determine the density of silicon atoms. The atomic mass of silicon is 28.09 g/mol, and its molar volume is 12.058 cm³/mol. Therefore, the density of silicon atoms can be calculated using the formula:

Density of silicon atoms = 1 / (Molar volume of silicon / Atomic mass of silicon)

Now we can calculate the density of free charge carriers in the Si crystal.

Please provide the molar volume of silicon and the atomic mass of silicon.