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Q E27

Posted: Thu Oct 04, 2018 5:19 pm
by Emily Orozco L4
Did anyone know how to find part A. I got part B but there's a step I'm missing because I have no idea where the answer from part A comes from.

Re: Q E27

Posted: Thu Oct 04, 2018 6:10 pm
by melodyzaki2E
If you start off with one molecule of water, you have to divide by Avogadro's number to convert the molecule to moles, and then you can multiply the mole by the molar mass of water to get grams. So you should end up with 2.991 x 10^-23 g/molecule. Does that make sense?

Re: Q E27

Posted: Thu Oct 04, 2018 10:46 pm
by Samantha Ito 2E
Since water has a molar mass of 18.02 g/mole, you can divide that by Avogadro's number in order to get g/molecule.
(18.02g/mol)/(6.022*10^23molecules/mol)=2.992*10^-23g/molecule

Re: Q E27

Posted: Thu Oct 04, 2018 11:14 pm
by AustinGrove3B
Find the weight of 1 mole of water. Remember each mole of a substance contains exactly 6.022*10^23 molecules of that substance. Therefore the weight of a mole of water divided by 6.022*10^23 would equal the weight of 1 water molecule.

Re: Q E27

Posted: Thu Oct 04, 2018 11:55 pm
by 005113695
To find the mass of one water molecule, divide it by Avogadro's number and then multiply it by the molar mass of water.