Answer: There are 0.00208 moles in 1.25 x 10^21 atoms of silicon.
Step-by-step explanation: To convert atoms to moles, we need to use the Avogadro’s number, which is the number of atoms or molecules in one mole of any substance. The Avogadro’s number is approximately 6.022 x 10^231. Therefore, to find the number of moles in a given number of atoms, we need to divide the number of atoms by the Avogadro’s number. For example, using the given data, we get:
moles = atoms / Avogadro’s number moles = 1.25 x 10^21 / 6.022 x 10^23 moles = 0.00208
This means that there are 0.00208 moles in 1.25 x 10^21 atoms of silicon. This conversion is useful for finding the mass or volume of a substance using its molar mass or molar volume.
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