105012653 1F
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What are the uses of Avogadro #? What's an example we would use it in?

Chem_Mod
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If you wanted to convert from moles into molecules. For example, the number of molecules of H in 1 mole of H would be 6.022x10^23 molecules.

404975170
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Avogadro‘s # is the number of particles, atoms or molecules that are in one mole. It can be applied when you have an amount given for moles and the question asks for it in atoms so you use dimensional analysis to convert values.

ElizabethP1L
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Avogadro's number is always 6.022*10^23. We mostly use it in stoichiometry. The most common uses for it is converting from moles to atoms. To do this, simply multiply the molar mass by Avogadro's number! To go from atoms to moles, divide the number of atoms you have by Avogadro's number. Hope this helped! :)

Miya Lopez 1I
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When a question asks you to find how many molecules there are of something, you would use Avogadro's number in your calculations. For example in E.29 (c)

"E.29 A chemist measured out 8.61 g of copper(II) chloride
tetrahydrate, CuCl2*4H2O. (a) How many moles of
CuCl24H2O were measured out? (b) How many moles of Cl
ions are present in the sample? (c) How many H2O molecules
are present in the sample? (d) What fraction of the total mass of
the sample was due to oxygen?"

You would multiply the number of moles of CuCl2*4H2O in 8.61 g by 4 moles of H2O over 1 mole of CuCl2*4H2O, and by 6.022*10^23 molecules (Avogadro's number).

0.0417 mol CuCl2*4H2O x 4 mol H20 x 6.022*10^23 molecules = 1.00*10^23 molecules of H20

Samantha Castro 1D
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By definition avogadro's number is exactly 6.022 times 10^23. This constant is used in stoichoimetry. For instance, it is used to convert from moles to atoms. Such as multplying the molar mass by avagadro's number.

Yitzchak Jacobson 1F
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I believe that Avogadro's number can be very useful when trying to do conversions in chemistry calculations. An example that can be considered is attempting to convert a calculation to particles per mole.

Taizha 1C
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What is a good way to determine when to used avogadro's #?

Chem_Mod
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Whenever you need to convert moles of objects to number of objects. Because avogadro's constant means 1 mole of object = 6.022 * 10^23 number of objects. the objects can be molecules, atoms, ions, electrons, etc.

Porus_Karwa_2E
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