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4 years ago

13

Find the number of free electrons per cubic centimeter in germanium at room temperature given that there are 5.6x10-10 free elec

trons per atom. The density and molar mass of silicon are 5.32 g/cm3 and 72.59 g/mol, respectively.

1 answer:

charle [14.2K]4 years ago

5 0

Answer:

$2.41 \times 10^{13}\ free\ electrons/cm^3$

Explanation:

given,

free electron per atom = 5.6 x 10⁻¹⁰

density of silicon = 5.32 g/cm³

molar mass of silicon = 72.59 g/mol

number of moles per cubic centimeter

= $\dfrac{5.32}{72.59}\ mole/cm^3$

number of atom per cubic centimeter

= $\dfrac{5.32}{72.59}\times 6.022 \times 10^{23}\ /cm^3$

number of free electron per cubic centimeter

= $\dfrac{5.32}{72.59}\times 6.022 \times 10^{23}\times 5.6 \times 10^{-10}/cm^3$

= $2.41 \times 10^{13}\ free\ electrons/cm^3$

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