Avogadro's numbers are used to convert the moles, atoms, and molecules. There are 51.17 × 10²¹ molecules in 8.5 x 10⁻² moles of HF.
Avogadro's number converts the moles into molecules with the help of the value of the Avogadro's number as 6.02 x 10²³.
We know that 1 mole of HF has 6.02 x 10²³ molecules
Then, 8.5 x 10⁻² moles of HF will have:
(8.5 x 10⁻²) × 6.02 x 10²³ = 51.17 × 10²¹ molecules.
Therefore, 51.17 × 10²¹ molecules are present in 8.5 x 10⁻² moles of HF.
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