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Posted: Sun Apr 15, 2018 11:15 pm
What are the uses of Avogadro #? What's an example we would use it in?

Posted: Sun Apr 15, 2018 11:22 pm
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.

Posted: Sun Apr 15, 2018 11:23 pm
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.

Posted: Sun Apr 15, 2018 11:23 pm
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! :)

Posted: Sun Apr 15, 2018 11:24 pm
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

Posted: Mon Apr 16, 2018 1:17 pm
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.

Posted: Sun Apr 22, 2018 11:50 pm
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.